Losing neutral is an emergency, but this I think might be losing a hot, which is less of an emergency but yet the same priority to the power company.
If half the house is solid, but the other half is flaky.... and if the breakers in question are in a pattern just like this (every other row of spaces which gets confusing where tandems are involved)... and if the problem mysteriously fixes itself when a 240V load is switched on... that's a lost phase/hot.
In that case, no appliances are in danger of over-voltage as would be the case in a Lost Neutral... however as far as the power company is concerned, the fix is exactly the same - get a boom truck out there and redo some splices.
"It's a Sunday"... Yeah we had the more insidious one, the Lost Neutral, and we called the power company immediately. They apologized and said they'd be about an hour, came out and fixed us up shipshape. In fact they fixed a neighbor, who had a flaky hot wire that was unreported - the worker had me notify them and cut their mains to avoid having to descend out of the bucket.