Just read this today.

"Any person who qualifies as a resident on August 28, 2019, and who does not own an AR-15 shall have one year to purchase an AR-15. Any resident qualifies as a resident after August 28, 2019, and does not own an AR-15 shall purchase an AR-15 no later than one year after qualifying as a resident."

HB 1108

https://www.house.mo.gov/billtrackin.../2290H.01I.pdf