Ive been here fully retired since 2019 . Starting getting benefits in 2020 but because of covid they just started mailing again in 2022 . So Ive had 2 experiences with mailing the letter so far
A word to the wise . My experience the past 2 years sending with tracking did not fare well . They never received it as it goes into a PO Box but tracking requires a signature . Past 2 years US mail has just lost it . My advice if you have to fill out the form here , put it in another envelope and send it tracking to a friends address and have them put a first class stamp on it and have them send it for you inside the US
It took me only 3 weeks but I used this service Highly recommended They do it all for you . I do my own visa extensions but for my passport I wanted it to be flawless . Look up Thai Visa Center . They were very good with corresponding quickly