Daleth Darko

I can confirm that this happens on the nintendo switch, my switch is up to date and unmodified. I use a game cartridge version of minecraft.

If you download the world and play on single player does it still happen?

You could try activating cheats and clearing your inventory via command, but take a backup of the world as it is going to disable achievements.

Having "2000 members" on your realm is really outside the scope of what realms was designed for considering they only intend 10 people to be on at a time. Try using an unmodified client aswell before reporting bugs. If you actually have 2000 players, you should really consider buying an actual minecraft server host elsewhere. I mean I am not saying that you're wrong to try to do it on realms, but a reasonable person would assume that a server you pay less than 10$ a month for was not designed for this kind of load.

All that in mind, there are issues with crashing and rollbacks, but honestly on my realm it happens twice a day tops at this point. I'd recommend trying to find a server host that is intended for this kind of load as at this point, I really don't think that's something you can fault them for when it crashes. 

(I am new here, so take what I say with a grain or two of salt)

As an added note, I'd recommend you thoroughly scan minecraft hacks before you install them, I took the time to do so for you here,  you may want to run some scans on your pc.

I did note that my world got rolled back about on the 14th, I was fighting the ender dragon and got kicked, logged back on in my base before the fight. Wasn't that far of a rollback, maybe 15 minutes tops, but still.

I am not entirely sure but I'd recommend trying to download the world, enable cheats, then reupload it. Realms can be a bit wonkey as of late.

I thought the same thing for a while, but, at least in my case, it turned out it just does not show a progress bar, you can check to see if it's uploading via the resource monitor or task manager and check what the network activity for minecraft is. It can take quite a bit of time to upload if your internet speed is too slow, try leaving it overnight. Also do not minimize mc, windows 10 apps "hibernate" or something when you minimize them, that will interrupt the upload.

Good luck.

I am having this issue as well on bedrock 1.13.2, it'd be nice if we could have some info about it..