Happened to me while I was home in Canada for a month - wet passport completely damaged
Got a new one using the expedited process
Visa/extension of stay/re entry permit all void.
Was able to get a new "sticker" for a new visa put into my passport from the Thai embassy (consulate?) in Toronto... Was able to sort it all out but a pretty expensive mistake!
, you won't ever need to do a "90" day report, because you "reset" everytime you re-enter.
You WILL need to register where you're staying, everytime you return. (first file from the hotel/SHA+ and then report once stationed in your residence.)
You will need most of the documents (proof of employment, gps/map location of your house (or the school/place of employment), various signed letters of proof from your employer) to be written in Thai (and some, such as your contract in both English and Thai) .....
Do you have all of the required paperwork already that you know of??