1.6TDI CR FAP: water pump leaking issue (?) : mileage or age?

As discussed in a parallel thread, I might have a leaking water pump, which might oblige me to have the cam done in my Octavia Combi II 1.6TDI CR FAP from sept. 2009, with about 125k km on the clock.

That known pump failure (leakage), is that something that's known to occur after a certain mileage, or after a certain number of years of age of the part?

Has anything been changed to the replacement pumps currently being provided which makes them less prone to spring leaks?

I might be in a position to decide whether I only have the pump replaced and keep the cam belt (plus other unused parts from the kit) in stock for a few years (up to about 6) until I'm closer to the 210k km mark at which the cam belt is programmed to be replaced. But for that I'd have to know how sure I am that the replacement pump will not then be approaching the mileage at which it is likely to spring a leak again.