"saves" is just server specific feature, have no relation to UO protocol.
It must be implemented by user, in case he need this, using journal workaround functions.
For instance, server i played have no such phenomenon as "save's lag" and users are not notifyed of this background process.
I play on Defiance, and the way the saves work is that it gives you a 30 second warning, and instead of saying "Saving world state..." it just brings up a gump with all this info, so you can't even use UO.InJournal anymore. Any suggestions for this ?
if you need press something on gump, read topics on gumps workaround using ,recall command. Search for this forum. Also you may read rgis in forum archive, FAQ branch.