I got a refund though which was a plus.

sync of what?

youre saves?

on what platform?

if youre referring to xbox one, then saves are stored locally and uploaded to the cloud. so you havent lost anything at all. its all there waiting to be synced.

going offline (unplug from router) should allow them to be used until servers catch up on microsofts end

not beths fault that microsoft servers are slow or in error

if youre referring to ps4. they are stored locally again, and uploaded to cloud later.

I lost literally every single save, cloud and local. I had to delete local saves to boot it out of the infinite load loop, then fallout 4 failed over 100 times to sync to cloud. Long story short everything is gone.

its impossible to lose cloud saves. they stored on servers.

they just werent syncing properly.

sounds like ps4 though because you cant check xbox one cloud storage.

so you wouldnt know if they were there or not.

Its xbox one, and my cloud saves are gone too. I spent 4 hours with tech support trying to fix it and nothing worked. Also it keeps getting stuck at 100% sync

I had the issue. I manually unplugged the console; logged into account again and it fixed it

That was one of the things we tested

Try logging out of your account; resetting your internet and console; they eject the game and re-insert. If this doesn't work I don't know

Like I said above, already did it. And I'll be damned if I play through all of that [censored] again just to have it [censored] up again and erase everything I did up until that point.

Note that Fallout 4 like all Bethesda games make large saves and it autosaves very often.
I had to turn off the Steam sync function as game generated safes faster than steam uploaded.