This is not a travel advice group, so I'm shutting this post down:
1. There is no restrictions or quarantine requirements to travel domestically, inside Thailand.
2. An airline, FOR DOMESTIC FLIGHTS, can accept whatever ID they want, including Thai drivers license, expired passports, etc - however don't expect your expired passport to be accepted. You will *NOT* cross immigration on a domestic flight.
3. >My passport has expired
I believe all extension of stay and visas are valid for the normal stamp, OR the length of the passport, whatever is shorter. The overstay fine is 500THB a day, with a maximum of 20K THB. After 90 days of overstay, if you turn yourself in to immigration, you will be deported to your home country at your own expense and blacklist for 1 year. If you are caught on overstay, the fine will be 20K THB and a blacklist of 5 years. If you can not afford a flight home, the Thai government charges a daily fee for the immigration detention center.
See
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for a graphic of the overstay fines, and
for an overstay video
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(since some people want to watch videos instead of reading simple graphics)
Both are from the Thai government
Good luck!
If someone wants this post reopen, send a mod a message and we'll re-open the post.