Looks like Blizz applied some bug fixes to Reckoning in patch 1.13.3.
I wanted to take a moment to provide some clarification around what changed in 1.13.3 with Reckoning. There were several systemic issues with extra attack procs behaving incorrectly, which we fixed in the patch. A secondary effect of these fixes were two notable changes to Reckoning:
Reckoning stacks are lost when you mount up.
Reckoning stacks are lost when you initiate an auto-attack against a target and cancel it before it goes off.
However, both of these behaviors were correct behaviors in the 1.12 reference client and as such are considered bug fixes. Both of these issues have been added to the “Not A Bug” list.
Additionally, when investigating the reports around this, we did discover another bug where Paladins will lose stacks of Reckoning if they are not facing their target or are out of range to attack the target when the Reckoning stacks are gained. This is not consistent with Reference client behavior, we have a fix for this now, and it should be fully live the next time we have realm restarts.
Lastly, while we appreciate the reports in this thread, there were many comments and replies that do not apply directly to this issue, or were unhelpful, and we’d like to remind everyone of the bug report forum guidelines 22. We will monitor and remove unhelpful or off-topic replies in threads like this. Keeping these threads on-topic and strictly comprising information that helps us find and reproduce bugs will help ensure that we can get these issues identified and fixed faster.
it was fun while it lasted :) the "extra atk" storage was prevalent on private servers but the table required to push off normal attacks was much smaller in Classic WoW, I was heavily sweating when people started making reddit posts about it...