I returned to Bangkok from Philippines on Saturday. I have retirement visa extension which expires in December and had reentry permit and 30 days covid insurance. At the Thaipass check station I had to show insurance certificate. At passport control they did not ask for insurance certificate. They stamped me in until December.
I have a 1 year retirement visa that's good until December. I returned to Thailand yesterday with 30 days of covid insurance. They stamped me in until December.
The agent can probably get a sooner amphur appointment, but give it a try. The documents, translations and 'legalization' of documents will be tricky. I didn't feel that I could do it with my very limited Thai language skill. You can always get an agent if you get stuck.
My wife. We got an agent to preserve our sanity then registered it at the Philippine embassy. The worst part was getting the documents the Philippines requires before issuing the certificate of legal capacity to contract marriage.