Context: Nimble Onslaught was removed in today's patch and replaced with Truly Nimble Onslaught. Old achievement is now missing if you hadn't already finished it.
AP hunting is a major part of why I play GW2, and generally speaking I focus on other areas of the game than LW because LW achievements are always there for me to get... Usually. The Nimble Onslaught achievement being removed _**without notification **_in this patch is a really big hit for that given the fact that to-date I have never missed a LW achievement across all expansions and all LW seasons.
As I understand from other threads, there was some exploit that caused an issue here that has since been addressed. Regardless, in the past cases where this has been a problem (ie. W4 Raid CMs), the old achievement has been left in while the new achievement was added. This is the right approach here so that no one misses that AP even if they get to it later.
I'd really like it if ANet would add it back. There is zero logical reason to remove the old achievement and make it unobtainable.
Valor Zeal [VZ] - Stormbluff Isle