diff --git a/bpf_progs/offload.c b/bpf_progs/offload.c
index 56ace19..2e339b2 100644
--- a/bpf_progs/offload.c
+++ b/bpf_progs/offload.c
@@ -131,7 +131,7 @@
                    TETHERING_GID)
 
 static inline __always_inline int do_forward6(struct __sk_buff* skb, const bool is_ethernet,
-        const bool downstream) {
+        const bool downstream, const unsigned kver) {
     // Must be meta-ethernet IPv6 frame
     if (skb->protocol != htons(ETH_P_IPV6)) return TC_ACT_PIPE;
 
@@ -305,13 +305,13 @@
 DEFINE_BPF_PROG("schedcls/tether_downstream6_ether", TETHERING_UID, TETHERING_GID,
                 sched_cls_tether_downstream6_ether)
 (struct __sk_buff* skb) {
-    return do_forward6(skb, /* is_ethernet */ true, /* downstream */ true);
+    return do_forward6(skb, /* is_ethernet */ true, /* downstream */ true, KVER_NONE);
 }
 
 DEFINE_BPF_PROG("schedcls/tether_upstream6_ether", TETHERING_UID, TETHERING_GID,
                 sched_cls_tether_upstream6_ether)
 (struct __sk_buff* skb) {
-    return do_forward6(skb, /* is_ethernet */ true, /* downstream */ false);
+    return do_forward6(skb, /* is_ethernet */ true, /* downstream */ false, KVER_NONE);
 }
 
 // Note: section names must be unique to prevent programs from appending to each other,
@@ -331,13 +331,13 @@
 DEFINE_BPF_PROG_KVER("schedcls/tether_downstream6_rawip$4_14", TETHERING_UID, TETHERING_GID,
                      sched_cls_tether_downstream6_rawip_4_14, KVER(4, 14, 0))
 (struct __sk_buff* skb) {
-    return do_forward6(skb, /* is_ethernet */ false, /* downstream */ true);
+    return do_forward6(skb, /* is_ethernet */ false, /* downstream */ true, KVER(4, 14, 0));
 }
 
 DEFINE_BPF_PROG_KVER("schedcls/tether_upstream6_rawip$4_14", TETHERING_UID, TETHERING_GID,
                      sched_cls_tether_upstream6_rawip_4_14, KVER(4, 14, 0))
 (struct __sk_buff* skb) {
-    return do_forward6(skb, /* is_ethernet */ false, /* downstream */ false);
+    return do_forward6(skb, /* is_ethernet */ false, /* downstream */ false, KVER(4, 14, 0));
 }
 
 // and define no-op stubs for pre-4.14 kernels.
@@ -362,7 +362,8 @@
 static inline __always_inline int do_forward4_bottom(struct __sk_buff* skb,
         const int l2_header_size, void* data, const void* data_end,
         struct ethhdr* eth, struct iphdr* ip, const bool is_ethernet,
-        const bool downstream, const bool updatetime, const bool is_tcp) {
+        const bool downstream, const bool updatetime, const bool is_tcp,
+        const unsigned kver) {
     struct tcphdr* tcph = is_tcp ? (void*)(ip + 1) : NULL;
     struct udphdr* udph = is_tcp ? NULL : (void*)(ip + 1);
 
@@ -552,7 +553,7 @@
 }
 
 static inline __always_inline int do_forward4(struct __sk_buff* skb, const bool is_ethernet,
-        const bool downstream, const bool updatetime) {
+        const bool downstream, const bool updatetime, const unsigned kver) {
     // Require ethernet dst mac address to be our unicast address.
     if (is_ethernet && (skb->pkt_type != PACKET_HOST)) return TC_ACT_PIPE;
 
@@ -640,10 +641,10 @@
     // if the underlying requisite kernel support (bpf_ktime_get_boot_ns) was backported.
     if (is_tcp) {
       return do_forward4_bottom(skb, l2_header_size, data, data_end, eth, ip,
-                                is_ethernet, downstream, updatetime, /* is_tcp */ true);
+                                is_ethernet, downstream, updatetime, /* is_tcp */ true, kver);
     } else {
       return do_forward4_bottom(skb, l2_header_size, data, data_end, eth, ip,
-                                is_ethernet, downstream, updatetime, /* is_tcp */ false);
+                                is_ethernet, downstream, updatetime, /* is_tcp */ false, kver);
     }
 }
 
@@ -652,25 +653,25 @@
 DEFINE_BPF_PROG_KVER("schedcls/tether_downstream4_rawip$5_8", TETHERING_UID, TETHERING_GID,
                      sched_cls_tether_downstream4_rawip_5_8, KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ true, KVER(5, 8, 0));
 }
 
 DEFINE_BPF_PROG_KVER("schedcls/tether_upstream4_rawip$5_8", TETHERING_UID, TETHERING_GID,
                      sched_cls_tether_upstream4_rawip_5_8, KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ true, KVER(5, 8, 0));
 }
 
 DEFINE_BPF_PROG_KVER("schedcls/tether_downstream4_ether$5_8", TETHERING_UID, TETHERING_GID,
                      sched_cls_tether_downstream4_ether_5_8, KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ true, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ true, /* updatetime */ true, KVER(5, 8, 0));
 }
 
 DEFINE_BPF_PROG_KVER("schedcls/tether_upstream4_ether$5_8", TETHERING_UID, TETHERING_GID,
                      sched_cls_tether_upstream4_ether_5_8, KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ false, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ false, /* updatetime */ true, KVER(5, 8, 0));
 }
 
 // Full featured (optional) implementations for 4.14-S, 4.19-S & 5.4-S kernels
@@ -681,7 +682,7 @@
                                     sched_cls_tether_downstream4_rawip_opt,
                                     KVER(4, 14, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ true, KVER(4, 14, 0));
 }
 
 DEFINE_OPTIONAL_BPF_PROG_KVER_RANGE("schedcls/tether_upstream4_rawip$opt",
@@ -689,7 +690,7 @@
                                     sched_cls_tether_upstream4_rawip_opt,
                                     KVER(4, 14, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ true, KVER(4, 14, 0));
 }
 
 DEFINE_OPTIONAL_BPF_PROG_KVER_RANGE("schedcls/tether_downstream4_ether$opt",
@@ -697,7 +698,7 @@
                                     sched_cls_tether_downstream4_ether_opt,
                                     KVER(4, 14, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ true, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ true, /* updatetime */ true, KVER(4, 14, 0));
 }
 
 DEFINE_OPTIONAL_BPF_PROG_KVER_RANGE("schedcls/tether_upstream4_ether$opt",
@@ -705,7 +706,7 @@
                                     sched_cls_tether_upstream4_ether_opt,
                                     KVER(4, 14, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ false, /* updatetime */ true);
+    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ false, /* updatetime */ true, KVER(4, 14, 0));
 }
 
 // Partial (TCP-only: will not update 'last_used' field) implementations for 4.14+ kernels.
@@ -725,13 +726,13 @@
 DEFINE_BPF_PROG_KVER_RANGE("schedcls/tether_downstream4_rawip$5_4", TETHERING_UID, TETHERING_GID,
                            sched_cls_tether_downstream4_rawip_5_4, KVER(5, 4, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ false);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ false, KVER(5, 4, 0));
 }
 
 DEFINE_BPF_PROG_KVER_RANGE("schedcls/tether_upstream4_rawip$5_4", TETHERING_UID, TETHERING_GID,
                            sched_cls_tether_upstream4_rawip_5_4, KVER(5, 4, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ false);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ false, KVER(5, 4, 0));
 }
 
 // RAWIP: Optional for 4.14/4.19 (R) kernels -- which support bpf_skb_change_head().
@@ -742,7 +743,7 @@
                                     sched_cls_tether_downstream4_rawip_4_14,
                                     KVER(4, 14, 0), KVER(5, 4, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ false);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ true, /* updatetime */ false, KVER(4, 14, 0));
 }
 
 DEFINE_OPTIONAL_BPF_PROG_KVER_RANGE("schedcls/tether_upstream4_rawip$4_14",
@@ -750,7 +751,7 @@
                                     sched_cls_tether_upstream4_rawip_4_14,
                                     KVER(4, 14, 0), KVER(5, 4, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ false);
+    return do_forward4(skb, /* is_ethernet */ false, /* downstream */ false, /* updatetime */ false, KVER(4, 14, 0));
 }
 
 // ETHER: Required for 4.14-Q/R, 4.19-Q/R & 5.4-R kernels.
@@ -758,13 +759,13 @@
 DEFINE_BPF_PROG_KVER_RANGE("schedcls/tether_downstream4_ether$4_14", TETHERING_UID, TETHERING_GID,
                            sched_cls_tether_downstream4_ether_4_14, KVER(4, 14, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ true, /* updatetime */ false);
+    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ true, /* updatetime */ false, KVER(4, 14, 0));
 }
 
 DEFINE_BPF_PROG_KVER_RANGE("schedcls/tether_upstream4_ether$4_14", TETHERING_UID, TETHERING_GID,
                            sched_cls_tether_upstream4_ether_4_14, KVER(4, 14, 0), KVER(5, 8, 0))
 (struct __sk_buff* skb) {
-    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ false, /* updatetime */ false);
+    return do_forward4(skb, /* is_ethernet */ true, /* downstream */ false, /* updatetime */ false, KVER(4, 14, 0));
 }
 
 // Placeholder (no-op) implementations for older Q kernels