My hotel had been told that the TM30 is no longer needed since Covid. They called the immigration office to confirm this but I took a photo of our booking just in case. The hotel also gave a business card and said if there's any problems get immigration to call.
Thanks - looks like we drive south from Chumphon and catch the car ferry to samui, then leave the car in samui, go to Tao and then return to collect it. Complicated but doable.