D3T are work for hire, and would not be able to continue on the game indefinitely. Seems the Japanese release was basically the deadline for getting as much sewn up as possible before the contract with SEGA ended.
If people want further patches the pressure should be put on SEGA from here on out, as long as it is done respectfully and maturely. SEGA have been known to patch games after the fact on occasion.
A lot of us had put considerable pressure on Sega for an extended period of time until about January or so, with many of us even reporting the same bugs multiple times. Personally, I have given up and came to accept the release in it’s current state.