Deadline looms for prepaid mobile users in Thailand to register
http://www.nationmultimedia.com/busi...-30252420.html
http://www.thaivisa.com/forum/topic/...d-to-register/
As I read it, the deadline might be 31 July 2015. As with all things here YMMV. Maybe pop round your provider on your next visit with your passport? We went through a similar exercise circa 2006.