Depends which immigration office! Unless things have changed, Jomtien (for example) don't like you going early and have sent people, myself included, away and said "come back with seven days left".
According to an article my uncle's second aunty (through marriage) heard from a Thai guy who was taught English by a Norwegian guy who was dating this Russian woman on Khao San Rd.
My sister said her boyfriend said his brother had read (on Facebook) that his uncle had seen that his wife's workmate said that a Thai friend had heard vai someone at immigration that told a bar girl that told her "boyfriend" that it would start at some point.
I think you have a lot of research to do rather than asking for otger Favebook users to supply you with solutions and "contacts".
If you want to so it the "not-so-legal' way, fins the nearest Visa Agent and go inside...
Otherwise, my advice would be to return to your home country and obtain a METV (if available to you) and come back to Thailand with that, at least. That, worked to it's maximum, will give you nine months of stay in Thailand. Id then leave for a week or so (Nice holiday to Malaysia or the like) and then come back with a Tourist Visa which will give you 30 days (currently but by then potentially 6o days) rhen extend that at the local immigration office (at a cost of 1900THB currently) for a further 30 days.