Penalty on ceiling on loss of EPR

[vikramcobra]

Hi, what is the reason for imposing penalty on ceiling on an A320 on the loss of EPR mode (either rated or unrated mode). In both the cases isn't the IAE engine capable of producing the same amt of thrust, for after all the engine performance is still the same.

2. What does the V and A 5 stand for in the IAE V 2527 A 5 stand for?

Thanks in anticipation