Dozy does raise a bit of a point there. I think many people can see a fair old downturn on the horizon or at least a high chance of one and three month “probation period” would take you neatly to just after Christmas… I wouldn’t put it past the more callous employers out there to use that to their advantage as you or anyone woukd be one of the last in, therefore one if the first out.
But having said that it depends on the job, sector etc etc