plugging espresso machine into timer?

[germantown rob]

No problem putting it on a timer. The Oscar would still need the steam valve opened to release the false pressure setting and a couple more minutes to recover. There is a valve on many machines that prevents the false pressure so not sure if you have that or not but either way you can still use a timer.
Leaving it on is the best answer since it still takes awhile for all the parts to get up to full temp and a cup warmer is a bit useless if you turn it on and off all the time.