This from the ARRL Southwestern Division e-Communicator:

"In 2020, the Yuma Hamfest, on February 14 and 15, will again be the ARRL Southwestern Division Convention. This is the convention that has rotated through the sections, and was conventionally held in September. There will not be another Southwestern Division convention in September in 2019 as no other groups have stepped up to sponsor such an event."

Marvin, KE6HTS