Essentially the technical unions walked out, leading to most of the technical staff spending transmission time outside the building. TV-am promtly sacked them but they stayed outside, while management and office staff tried desperately to keep the station on the air. TV-am was apparently almost bankrupted in the process.
I don't know about that, the strike started in November but Bruce Gyngell said that they could easily keep the management-run service going indefinitely, I think they had enough advertising to keep going until at least March. It's not entirely the case that ratings rocketed during the strike, it's often been said but in fact they started fairly constant - adults switched off but loads more kids switched on because obviously all the boring news was replaced by Batman.
My first memory of the TVam strike is the Wide Awake Club being a repeat and, in the ad breaks, Tommy Boyd came on to tell us it was a repeat so you shouldn't write in about anything. Initially there was no live programming at all, just repeats, but after a week they were able to do half an hour of live output a day, then an hour and by February they'd managed to get the repeats down to an hour a day and were broadcasting live for the other two and a half, but it was still utterly shambolic.
TVam always had problems with the unions, when they started they weren't allowed to do any live shows at the weekend because the unions refused. But they did very well out of the strike, they made tons of money.