It would be cool if these updates were seamless... The UX of losing service each time an update needs to be applied kind of sucks. Surely you could setup some mirroring? apply the updates on the mirrored version, then flip the switch and sync any data mismatches there after.
I could understand it being difficult with some major updates, but the majority should happen with no service interruption.... it's one of the things Onshape claim won't happen. Time will tell if that happens in practice.