Don't worry the MRA4 will have increased endurance and greater serviceability, therefore we don't need to replace the MR2 one for one.
Well that was the excuse a few years ago when 21 erm, 15 oh no, 12 were on order. Great spin until one goes u/s and leaves a bigger gap in cover, and it can't be in 2 places at once.
It now seems that the only driving force for numbers is cost, but how many do we really need? Why did they need 3 prototypes for 9 production aircraft, seems rather a lot?
Still good news that it's progressing, looks like we will see the MRA4 in a museum and as a gate guard before the MR2!