diff --git a/src/data/Thread.js b/src/data/Thread.js
index 92ffc49..5df777e 100644
--- a/src/data/Thread.js
+++ b/src/data/Thread.js
@@ -143,7 +143,7 @@ class Thread {
       dm_message_id: msg.id
     });
 
-    // The 1970 check is a knex bug, see https://github.com/tgriesser/knex/issues/1276
+    // The string type check is due to a knex bug, see https://github.com/tgriesser/knex/issues/1276
     if (this.scheduled_close_at && typeof this.scheduled_close_at === 'string') {
       await this.cancelScheduledClose();
       await this.postSystemMessage({
diff --git a/src/main.js b/src/main.js
index 0fbcc99..099e196 100644
--- a/src/main.js
+++ b/src/main.js
@@ -256,7 +256,8 @@ addInboxServerCommand('close', async (msg, args, thread) => {
   if (args.length) {
     if (args[0] === 'cancel') {
       // Cancel timed close
-      if (thread.scheduled_close_at) {
+      // The string type check is due to a knex bug, see https://github.com/tgriesser/knex/issues/1276
+      if (thread.scheduled_close_at && typeof thread.scheduled_close_at === 'string') {
         await thread.cancelScheduledClose();
         thread.postSystemMessage(`Cancelled scheduled closing`);
       }