I don't know how a software would know the backups are complete. Sometimes the backup take 10 min, sometimes they take 2 hours.
The software backing up knows and then triggers the sleep.
anyway, energy saver is fine -- except does anyone know why in 10.5 set to Never you could sleep at night, but with 10.6 set to Never you cannot sleep?
10.5 doesn't work as you describe unless you use the Schedule function I mentioned or used 3rd party software.
Kevin's original solution is fine except I wonder what would happen if I woke the computer after the 11pm schedule to sleep/ sliders set to never.
It would then stay awake. Sounds like you should just use the key command I mentioned to Sleep since that'll do it when you want it to do it no matter when.
I would then have to do a manual sleep. With Snow Leopard I may have to manually redo the sliders -- big hassle.
You mean redo the slider each time you wake so it can sleep later. That's just silly. Just use the key sequence.