How soon can I apply for my third COVID extension in Thailand before my current visa expires?

Hi everyone, thanks in advance for your help with my inquiry. I arrived in Thailand on Sept. 18th on a visa exempt (on-arrival) and have since done a 30 day extension followed by 2 COVID extensions. I am hoping to get a third COVID extension before my current one expires on March 29. Does anyone know how soon I can go in to apply for my third COVID extension? I read somewhere on here that I can do it within 30 days of the expiration date, but also found another resource that says I can only apply within 5 days of my expiration date.

When I can re-apply will determine whether I will try to do it at Surat Thani or Hua Hin. If anyone has any insight on the processes at those offices, I am all ears. Thanks again for your time and guidance.