You are right they have had a call out rota for years but it was an option to be on it... now it is being said that you "have" to be on it, a big difference in my opinion, The Company sounds like it's in a right mess as most of the engineers are only waiting for redundancies... Been beaten to death with the HR stick by the sound of it... Tracker watching to catch people out with time discrepancies etc... The good will has gone it's only downhill now. Time will tell that's for sure.