The latest beta includes some changes to /timer -p and adds a /timer -P.

The issue fixed with /timer -p is that it was not counting down repetitions. In other words, /timer -p was stopping the timer alias from being executed during the seconds count down for one repetition. /timer -r would then resume it for subsequent repetitions. The new /timer -p makes it count down across repetitions, so it will count down and skip repetitions during a pause and may even halt if it reaches the end of the repetition count. This is a significant change in behaviour but it seems to be in line with what was originally intended.

The new implementation of /timer -P pauses the timer completely. If anyone has a chance to test this out, please let me know if it is doing what was requrested in the original post.