Rita is 20 same age as Kingda Ka would have been and Top Thrill Dragster both now removed, Spinball Whizzer is 21 and was a cheap addition to add more capacity to the park when it was being brought out by Merlin. And Galactica being the original Prototype B&M Flying Coaster it will likely age with more issues.Yet again, citation very much required.
I know none are new, and may need occasional "bits", but end of life?
I'm no engineer, but not really.
So Alton Towers have themselves in a bind after years of neglect where the rides are aging.