>My PUTM is set to expire in less than 30 days. It would be nice to be notified perhaps only a few times during the 30 days. It is very annoying to see the pop-up window every time I log in or have to refresh the website.

Agreed, it is annoying. It worked, however, I got sick of it in about two days and paid up right away :)

Maybe it could be reduced to something like:

IF days_left < 31 AND MOD(DAY(DATE()),2 or maybe 3) = 0
popup the reminder
ENDIF