diff --git a/.travis.yml b/.travis.yml
index b251f496b07fdca4df01d3c719c312d5df3c0794..896c00597bb40db8fffa2e56d3dc40f338314d17 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -32,7 +32,7 @@ script:
   - cmake .
   - make
   - ulimit -c unlimited -S
-  - ./picoquic_ct && RESULT=$?
+  - ./picoquic_ct -x fuzz && RESULT=$?
   # Early out if the program exited successfully
   - if [[ ${RESULT} == 0 ]]; then exit 0; fi;
   - for i in $(find ./ -maxdepth 1 -name 'core*' -print); do gdb $(pwd)/picoquic_ct core* -ex "thread apply all bt" -ex "set pagination 0" -batch; done;
diff --git a/picoquic/logger.c b/picoquic/logger.c
index e2a74c2ea1d1b20fdae390852d96d664c589d56d..26fbfac39846366a0a1ab53400af8850d7db7ff8 100644
--- a/picoquic/logger.c
+++ b/picoquic/logger.c
@@ -403,13 +403,7 @@ void picoquic_log_retry_packet(FILE* F, uint64_t log_cnxid64,
     uint8_t unused_cil;
     int payload_length = (int)(length - ph->offset);
 
-    if (ph->vn == PICOQUIC_SEVENTH_INTEROP_VERSION) {
-        odcil = bytes[byte_index++];
-        unused_cil = 0;
-    }
-    else {
-        picoquic_parse_packet_header_cnxid_lengths(bytes[byte_index++], &unused_cil, &odcil);
-    }
+    picoquic_parse_packet_header_cnxid_lengths(bytes[byte_index++], &unused_cil, &odcil);
 
     if (unused_cil != 0) {
         /* malformed ODCIL, or does not match initial cid; ignore */
diff --git a/picoquic/packet.c b/picoquic/packet.c
index c60b5588368d2f88f753a02f47de72247b4d4dc5..9e5d9aff64e90d9634c0537450724f7e467286d3 100644
--- a/picoquic/packet.c
+++ b/picoquic/packet.c
@@ -716,15 +716,10 @@ void picoquic_queue_stateless_retry(picoquic_cnx_t* cnx,
         byte_index = header_length = picoquic_create_packet_header(cnx, picoquic_packet_retry,
             0, bytes, &pn_offset, &pn_length);
 
-        /* Draft 13 requires adding the ODCID, no frames  */
-        if (picoquic_supported_versions[cnx->version_index].version ==
-            PICOQUIC_SEVENTH_INTEROP_VERSION) {
-            /* Old: encode ocdil as single byte */
-            bytes[byte_index++] = cnx->initial_cnxid.id_len;
-        } else {
-            /* new: use same encoding as packet header */
-            bytes[byte_index++] = picoquic_create_packet_header_cnxid_lengths(0, cnx->initial_cnxid.id_len);
-        }
+        
+        /* use same encoding as packet header */
+        bytes[byte_index++] = picoquic_create_packet_header_cnxid_lengths(0, cnx->initial_cnxid.id_len);
+
         byte_index += picoquic_format_connection_id(bytes + byte_index,
             PICOQUIC_MAX_PACKET_SIZE - byte_index - checksum_length, cnx->initial_cnxid);
         byte_index += (uint32_t)data_bytes;
@@ -871,13 +866,8 @@ int picoquic_incoming_retry(
         uint8_t odcil;
         uint8_t unused_cil;
 
-        if (ph->vn == PICOQUIC_SEVENTH_INTEROP_VERSION) {
-            odcil = bytes[byte_index++];
-            unused_cil = 0;
-        }
-        else {
-            picoquic_parse_packet_header_cnxid_lengths(bytes[byte_index++], &unused_cil, &odcil);
-        }
+        picoquic_parse_packet_header_cnxid_lengths(bytes[byte_index++], &unused_cil, &odcil);
+
 
         if (unused_cil != 0 || odcil != cnx->initial_cnxid.id_len || odcil + 1 > ph->payload_length ||
             memcmp(cnx->initial_cnxid.id, &bytes[byte_index], odcil) != 0) {