Not a bad idea, except I didn't notice for ages that the base was on red alert. I can't even remember there being a mission indicating the base was under attack. So there are no saves to revert back to.
At the time the base was in the process of being built, it had some grunts, storage, power, weapons stash, radar and laser turrets, but not much else so was ignoring it until I got the popup saying the labs / workshops had been built.
I usually save every other day into different slots, so by the time I spotted it I'd overwritten every save from before the red alert.