My 30 days runs out on the 20 th March. I'm going to Chiang Mai on the 15th. Should I get the extension before I go or is it easy to get up there. Where is the office in Chiang Mai? Am I able to get it a week before it runs out because I would consider getting it on Monday before I leave? Where is the closest office to Asoke? Sorry for so many questions.

It will be easy to get in Chiang Mai. The office is close to the airport.

You can get it a week early without a problem.

The only office you can use in Bangkok is at Chaeng Wattana. Map and info for getting there is here: http://bangkok.immigration.go.th/en/location1.html