A: Due to ShoPro falsely blocking and demonitising a lot of episodes on YouTube, I've had to upload them here so they can still be seen. To pay for hosting costs and the like, some episodes are limited to supporters of my Patreon.
A: That seems complex at first, but is a very simple system. Alternating episodes (starting from Ep63 of Season 1) are Patron episodes. This means 63 is Patron, 64 is free, 65 is Patron, etc.
Each subsequent season has the first 5 or 6 episodes free; whichever ensures that the finale of the season is always free.
In the case of two-parter episodes, they'll either both be free, or both be Patron. Essentially they're counted as one episode in the alternation, even though they're released individually.
Season 6 is a special case. As it's a future season, it's currently fully exclusive to Plusle Tier (and higher) Patrons. When the main series of PokéSins catches up to it, it'll begin to alternate like all the others. When that happens the Plusle Tier will get a different future season as their exclusive.
Okay... When written out it sounds more complex than it is. I explain with visuals in THIS G-LOG from 2020.