I'll never really understany why people are so focussed on the payment deadline. It really doesn't make sense at all in this case.
In fact DC actually gains the most, in theory, by releasing the game at the end of the month. He always gains a huge number of new supporters each update and if it's close(ish) to the end of the month, there's a high chance that many of them stay to get billed twice, once when they become a patron and right away again for the next month. Releasing it at the beginning of the next month, on the other hand, means they have 4 weeks to cancel their pledge again.
I mean, those who don't want to give him money can just stop pledging and play the game for free? There's no reason to pay money to him unless for those who like what he's doing.
PS: Having that all of that, I've seen no indication that DC actually cares about these details, at all. People are making these arguments for years and he continues to release the updates whenever they are done without any pattern.
PPS: The average patron pays him $2.60 a month (most of them $1-5 actually) and thus probably doesn't care at all about that kind of money. People always act like somebody is handing $66k over to DC while in fact he makes that much because he simply has a shit-ton of patrons who each give very little.