Sorry, I'm getting a little tired with hearing about how cabin crew are fearful of seeing their income diminish in future years. In a previous job a proportion of my total salary was made up from overtime and call out payments. I was unhappy about having an income that depended on the vagaries of the business, so I sought employment elsewhere. I took a slight drop in salary in the first six months but at least I knew that it was all consolidated pay. I would have thought that if cabin crew were concerned about the variability of their pay, that they would have got their union to negotiate for a higher percentage to be consolidated. Doesn't seem to have been happening though.
On top of that is this notion of a job for life. Look around you. The catering staff found they were sold off to Gate Gourmet. The engineering staff in wheels and brakes got sold off along with other parts of the engineering division. A number of the head office functions have been outsourced to India. These areas didn't get the relative shelter of BA employing new staff on a lower starting salary. The jobs simply ceased to be done inhouse. It may sound awfully harsh, but cabin crew have been protected by weak management who were more into empathy and appeasement and a union that was able to run rings around them. It was bound to change at some point. Welcome to reality.