My file was sent to MOI in April 2019 and received in May that year, so I am celebrating my 5-year anniversary of waiting for the interview. I plan to retire in six years, and I hope the process will be completed by then.
Of course, before I applied for citizenship, I had to have my PR for 5 years. And in order to apply for the PR, I had to be on the same work permit for 3 years. From PR application to getting it took 6 years, that's 14 years. I lapsed 1 year before applying for citizenship (lazy me!) and have now been waiting for my interview for 5 years.
So, we are talking 20 years and no end in sight. One thing you learn in Thailand is patience. 🙂