If that was when demo charges were still busted OP against buildings and it happened to that, then it doesnt count
Doesn't matter the cause. You've always been able to repair base buildings and I don't see a good reason for why it needed to be removed.
I'm just assuming here that you're allowed to repair the base up until it hits 0 HP, because that's not idiotic. I don't see how this is healthy in any way. Get some artillery, hit the enemy base, then rush it with a bunch of tanks. Knock it out, and then what? Literally no way to come back from it. Doesn't make any sense.
And if you can't repair the buildings, that's even worse. Hello artillery spam. Let's call a spade a spade here and admit this is a shit change.
EDIT: Hopefully I'm misunderstanding OP, and they just mean you're not allowed to repair the building until it's broken. Still. that's stupid and there's no reason it should be a thing.