Can I start my marriage visa extension 45 days before expiration in Thailand?

Hi, am I right in thinking that 45 days before expiration is the earliest I can start my marriage visa extension?

Master of bad timing, my visa expires mid April and I’d really like to get the paperwork in, the wheels turning and head south of Chiang Mai early March.

Thank you and seasons greetings to all the admin, y’all do an amazing job. 🙏