To be a bit picky the 1987/1988 TV-am industrial dispute was not a strike as such. There was a one day strike done by the union ACTT on Monday 23rd November 1987, and they were are expecting to return to work the following day, however TV-am MD Bruce Gyngell decided that anyone who went out on strike on that day would never return, and on the following morning he locked them all out.
The ensuing debacle was not a strike, as the workers were all willing to come back in, however they were locked out, as Gyngell had enough of the power of the ACTT union and wanted to teach them a lesson, which he did.
The first week or so without the main staff saw TV-am really reduced to showing non stop cartoons, Flipper, Batman, Happy Days, literally anything they could get to fill the three and half hours, alongside studio links and the odd news headlines with no video reports.
Gradually by December 1988 they managed to coax a number of main staff back who broke the picket line, and they produced a reduced version of Good Morning Britain from 8.00am, with the remainder of the morning the usual bag of cartoons and US imports, mashed together with repeats of interviews and segments they had in their archive.
Gradually too the TV-am newsroom could provide more news coverage, with access to certain news agency reports and videos from other sources.
All this led to Gyngell sacking the 200 or so ACTT members by the Spring of 1988 and hiring non-union staff from UK and Australia. Gyngell won, and the unions knew that their stranglehold on ITV was over. No more 1979 style strikes.
In the book "Morning Glory" part of the strike service was an interview at 8.30 by Anne Diamond. She slept in the house TVAM had on the premises. (Does anyone know anything about that house?)