diff --git a/src/generator.c b/src/generator.c
index dd8182ec..a0a60718 100644
--- a/src/generator.c
+++ b/src/generator.c
@@ -1512,7 +1512,7 @@ static proxy_instance_t *create_subproxy(proxy_instance_t *proxi)
 	subproxy->ckp = proxi->ckp;
 	subproxy->cs = ckzalloc(sizeof(connsock_t));
 	subproxy->si = proxi->si;
-	subproxy->id = proxi->subproxy_count++;
+	subproxy->id = proxi->subproxy_count;
 	subproxy->auth = proxi->auth;
 	subproxy->pass = proxi->pass;
 	subproxy->proxy = proxi;
@@ -1532,6 +1532,7 @@ static bool recruit_subproxy(proxy_instance_t *proxi, int epfd)
 	}
 
 	mutex_lock(&proxi->proxy_lock);
+	proxi->subproxy_count++;
 	HASH_ADD_INT(proxi->subproxies, id, subproxy);
 	proxi->client_headroom += proxi->clients_per_proxy;
 	mutex_unlock(&proxi->proxy_lock);
@@ -1808,11 +1809,13 @@ reconnect:
 	if (proxi != cproxy) {
 		proxi = cproxy;
 		if (!ckp->passthrough) {
+			proxy_instance_t *proxy = proxi->proxy;
+
 			connsock_t *cs = proxi->cs;
 			LOGWARNING("Successfully connected to proxy %d %s:%s as proxy",
 				   proxi->id, cs->url, cs->port);
 			dealloc(buf);
-			ASPRINTF(&buf, "proxy=%d", proxi->id);
+			ASPRINTF(&buf, "proxy=%d:%d", proxy->id, proxi->id);
 			send_proc(ckp->stratifier, buf);
 		}
 	}
diff --git a/src/stratifier.c b/src/stratifier.c
index c5569562..df2f15be 100644
--- a/src/stratifier.c
+++ b/src/stratifier.c
@@ -1006,6 +1006,7 @@ static sdata_t *duplicate_sdata(const sdata_t *sdata)
 	memcpy(dsdata->donkeytxnbin, sdata->donkeytxnbin, 25);
 	randomiser = ((int64_t)time(NULL)) << 32;
 	dsdata->blockchange_id = dsdata->workbase_id = randomiser;
+	cklock_init(&dsdata->workbase_lock);
 	return dsdata;
 }
 
@@ -1105,10 +1106,10 @@ static proxy_t *current_proxy(sdata_t *sdata)
 static void update_subscribe(ckpool_t *ckp, const char *cmd)
 {
 	sdata_t *sdata = ckp->data;
+	int id = 0, subid = 0;
 	const char *buf;
 	proxy_t *proxy;
 	json_t *val;
-	int id = 0;
 
 	if (unlikely(strlen(cmd) < 11)) {
 		LOGWARNING("Received zero length string for subscribe in update_subscribe");
@@ -1122,11 +1123,13 @@ static void update_subscribe(ckpool_t *ckp, const char *cmd)
 		return;
 	}
 	json_get_int(&id, val, "proxy");
+	json_get_int(&subid, val, "subproxy");
 
-	LOGNOTICE("Got updated subscribe for proxy %d", id);
+	LOGNOTICE("Got updated subscribe for proxy %d:%d", id, subid);
 
-	proxy = proxy_by_id(sdata, id);
+	proxy = subproxy_by_id(sdata, id, subid);
 	proxy->notified = false; /* Reset this */
+	sdata = proxy->sdata;
 
 	ck_wlock(&sdata->workbase_lock);
 	proxy->subscribed = true;
@@ -1883,14 +1886,15 @@ static char *stratifier_stats(ckpool_t *ckp, sdata_t *sdata)
  * first notify data comes from this proxy. */
 static void set_proxy(sdata_t *sdata, const char *buf)
 {
-	proxy_t *proxy;
-	int id = 0;
+	proxy_t *proxy, *subproxy;
+	int id = 0, subid = 0;
 
-	sscanf(buf, "proxy=%d", &id);
+	sscanf(buf, "proxy=%d:%d", &id, &subid);
 
 	mutex_lock(&sdata->proxy_lock);
 	proxy = __proxy_by_id(sdata, id);
-	sdata->proxy = proxy;
+	subproxy = __subproxy_by_id(proxy, subid);
+	sdata->proxy = subproxy;
 	mutex_unlock(&sdata->proxy_lock);
 
 	/* We will receive a notification immediately after this and it should