Come 20 Mar 16 the bell will toll for overstayers with over a 90 days overstay for those who surrender themselves, but for those who get arrested it appears there is no 90 day grace period if I'm reading the announcement right.
If I was an overstayer of over 90 days I would definitely exit Thailand before the rules go into effect 20 Mar 16 in order to avoid a long ban on reentry. Get legal on your stay or possibly say goodbye to Thailand for a year (or many more depending on overstay length) once identified as an overstayer.
Actually, I'm somewhat surprised the govt is actually putting it into effect but it does appear it's going into effect 20 Mar 16.
Edited by Pib, 2016-01-12 09:26:01.