I think the MRA4 unfortunately suffered from the "perfect storm" of things conspiring against its smooth introduction into service.
For example, I believe, from the second hand information I was hearing, that the recently created MAA wanted to be "whiter than white" in ensuring the MRA4 was "safe" for entry into service, no doubt understandable in the light of XV230 and the H-C report. No doubt this lead to some inevitable bureaucratic delays, which may have appeared from the outside to be technical faults.....
However, I can't claim to have much personal insight into this side of things.