[Critical] Save file corruption when server hoping while a map update gets released

Summary

This is a menacing new issue for us, where our players have reported loss of their entire save file for the map. Since all 4 reports happened when we updated the map and no reports after that (we didnt release an update) and based on what we gathered from playtesters, engineers and our players, it seems to happen when you server hop when a new update is released (we are not sure about the timing). This issue seems to have existed for a while now, because I have seen it since the 1.0 days, just never had a clear understanding of what causes it, so this is the closest we ve been to understanding it. We had 4 cases of save corruption happen in 2 days (2 per update we did). We only use Verse persistence.

Please select what you are reporting on:

Unreal Editor for Fortnite

What Type of Bug are you experiencing?

Verse

Steps to Reproduce

Create a verse script that saves heavily on the player (for better repro, make it be varied and a lot of things)
Create a code and have a player play it
While they are playing, enable another version of the game (through creator portal)
Have player leave game and rejoin.
(If it doesnt happen, keep trying, we dont know the exact conditions of the corruption, just know that its related to map updates)

Expected Result

Player keeps persistence on next match

Observed Result

Player starts with no persistence data when they should have it.

Platform(s)

PC

Save file corruption is pretty big this should get Looked at

FORT-1082888 has been created and its status is ‘Unconfirmed’. This is now in a queue to be reproduced and confirmed.

Want to also note that in our map (CHC), when trying to publish a new update, the verse persistence check takes a good 5-7 mins to complete, which seems abnormally long