This just in from Dorna:
2021 Thai GP cancelled
Wednesday, 21 July 2021
The FIM, IRTA and Dorna Sports regret to announce the cancellation of the OR Thailand Grand Prix, which was set to take place at Chang International Circuit from the 15th to the 17th of October. Despite the best efforts of all parties involved, the ongoing Covid-19 pandemic and resulting restrictions have obliged the cancellation of the event.
The FIM MotoGP World Championship looks forward to returning to race in front of the incredibly passionate Buriram crowd in 2022.
A replacement event is currently under consideration and any updates regarding a possible substitute will be published as soon as available.