I can't seem to find any info on this anywhere, but a quick question about Champion Masteries.

I'm sorry if this has become a redundant question, but I seriously can't find a simple, straight answer on any Google or forum search. All I'd like to know is will your level five masteries be reset back to level one at the end of season six? Is it pointless to try and gain level five on as many champions as you can? I was under the impression that as they add tiers to the mastery list, a level five mastery would come to mean that you're simply competent and experienced enough with that champion to know how to play him/her, and what to expect when playing against them. I'm taking level six to mean you're pretty good, and when they add level seven, it will likely be on a grounds that you can only achieve with one of the few champions you main. If the masteries get reset every season - especially the lower level masteries - then what exactly is the point?