Seems to happen more often after a restart, after the first 404s it will eventually start pulling posts properly then at some point the connection will go stale and it'll 404 again. It's pretty consistent for me. About to try it out on the latest pull. Nothing in the logs/dev mode. Just 404s in the console.
@julian Thank you Julian.
Tried to debug the recentreplies.js and found that it tries to access value of category that is undefined and all other fields of the post is set to null.
The idea is to try fix it in redis before upgrading.
If you would have a chance to advice me a correct direction where I should dig in in order to delete this corrupted data in db it will be super helpful.