We've also been experiencing this issue! The reset happens sometime between when we log out and log back in. I've noticed it happening for several versions now, but it's gotten much worse in 1.16.1: the resets are now happening several times a day and reset hours of progress at a time. We found that coordinating with everyone on the realm to log out every 30 minutes and stay offline for 8 minutes effectively forces the world to save, but that's still very inconvenient.
We've also been experiencing this issue! The reset happens sometime between when we log out and log back in. We found that coordinating with everyone on the realm to log out every 30 minutes and stay offline for 8 minutes effectively forces the world to save, but that's still very inconvenient.
This exact issue has been happening on my Java realm as well, but the amount of times it has happened has dramatically increased since the 1.16.1 update.