On this thread HERE it seems that Hank has put a new driver in the D1.
User cuberS seems to have a D1 with an ATtiny1634 (he has flashing pads and the MCU signature matches the ATtiny1634), but I haven’t find any firmware in the repository for such a light. He flashed the ATtiny85 firmware and it does not work. Is there a firmware he can flash to rescue his light?