its mostly correct. if you've met your promises thus far with no complaints, the post season doesn't matter, it can't hurt you. it does count if you are behind on promises though, those games can help save your bacon. i think after the 2nd or 3rd CT game is the last time you can get a message of OK-ness, but i actually think all the games after can help you.
i do believe even if you had a complaint, and since met it, you are clear to ignore those promises for the CT finals and NT. i am not clear that you are ok to ignore those before that final ok message can come in. personally, if i had a complaint, i would not stop meeting that promise until the CT finals (i can't remember if its after 2 games or 3 of the CT, when that final ok can come in, these are the kinds of details i lost after not coming around for a couple years, someone else probably knows. plus they've jacked with promises several times and i've never cared enough to re-establish the boundaries and edge cases).