diff --git a/libccp b/libccp
index e40be98..90847f3 160000
--- a/libccp
+++ b/libccp
@@ -1 +1 @@
-Subproject commit e40be98e2dd59f602e29c8b76fe9ec297e59b339
+Subproject commit 90847f3e5f86f882d36aae20ff1b063fb6382569
diff --git a/tcp_ccp.c b/tcp_ccp.c
index 0e9b03c..52cf5a1 100644
--- a/tcp_ccp.c
+++ b/tcp_ccp.c
@@ -79,6 +79,10 @@ static u32 ccp_now(void) {
     return tcp_jiffies32;
 }
 
+static u32 ccp_since(u32 then) {
+    return jiffies_to_usecs(tcp_jiffies32 - then);
+}
+
 static u32 ccp_after(u32 us) {
     return tcp_jiffies32 + usecs_to_jiffies(us);
 }
@@ -298,6 +302,7 @@ static int __init tcp_ccp_register(void) {
         .set_rate_rel = &do_set_rate_rel,
         .send_msg = &nl_sendmsg,
         .now = &ccp_now,
+        .since_usecs = &ccp_since,
         .after_usecs = &ccp_after
     };