Classic Mount collecting achievement not updating properly

Ive been having a problem with my mount achievement not updating properly. I understand the whole concept of it only tracks the character who can use the highest amount, but the issue I am having is that the counter does not update unless I specifically learn the mount on the character with the highest number of available mounts.For example, this morning I had 231 mounts being tracked for the achievement on my paladin. I then learned the heavenly golden cloud serpent mount on my warrior, and an Argent Tournament mount on my mage. This should put the counter at 233. If I look at the WowHead mount tracker for my paladin, it does in fact show 233.However, if I log onto my paladin, the mount counter for the achievement is still set at 231. BUT, I then learned a Mark of Honor mount ON MY PALADIN, and I watched the achievement tracker instantly jumped to 234 (which is correct).So what am I doing wrong? I know the achievement tracker has given people trouble before but I have not seen this issue before. via /r/wow https://ift.tt/2DtH7jh