No advice to add to what has already been said... just a funny story:
I had both wheels off a bike once - on the center stand, rear wheel removed first. Then I propped the front of the frame up with a piece of wood and removed the front wheel - it all looked just a bit dicey, but I actually was surprised how stable it was working on the bike with both wheels off.
As it was front-heavy even without the wheels, it seemed fine without any support beneath the rear end, just the two-point center stand and single front brace - until I made the mistake of casually leaning on the seat - I think I had the manual open there. The bike slowly tipped back - not enough to dump it, but
just enough for the front brace to drop to the floor. And there I was, holding the bike, with no wheels, balanced on just the center stand, wondering what the heck are you gonna do now, dumbass?!?
There was a plastic milk crate just close enough for me to reach out with my foot and slide it beneath the rear end to help hold the bike steady enough to reset the front brace - after which I promptly made one for the rear, propping it up by the axle in the swingarm as well...