alternatehistory.com

So, by 1950 the royal Navy has the following carrier classes

2 modernized Implacables
4 Centaurs (to be modernized in the 50's, acording to available budgets, they could be cut to two modernized)
4 Maltas being build and slowly entering service (then again, could be cut to two if budgets are slashed)

every other carriers (essentially worn out WWII veterans like Illustrious, plus all the light and small carriers) has been either scrapped or sold to foreign countries.

By 1960 the situation has evolved as follow

As feared, budgets were slashed. So only two Maltas were build, with two modernized Centaurs. The Implacables were to be converted into commando carriers, but two un-modernized Centaurs got the job instead, and the two Implacables were retired in 1959.

The RN is thus now a six carrier forces, two 28 000 tons Centaurs plus two 55 000 tons Maltas attack carriers with Buccaneers, plus two other Centaurs as commando carriers with helicopters.

Whatever funding available in the 60's will go to the Malta first, as they are the only one big enough to handle supersonic interceptors - be them British, French, or Americans.

As for the Centaurs, they will be modernized for Buccaneers but they can't handle supersonic fighters, so they will probably follow their elder sisterships as commando carriers in the late 70's.