I did look at the guideline and found this (5):Trialware is not allowed in the repository. It’s perfectly fine to attempt to upsell the user on other products and features, but a) not in an annoying manner and b) not by disabling functionality after some time period. …
Sorry, but imho this plugin does not agree with the guidelines. And, quite honestly, I do not mind paying for good software (and yours is good) but I appreciate being told right at the beginning.