Endwalker was an outlier as it was pushed back due to 2020. Dawntrail released in July, back on the original expansion release schedule.

Previous fan fests were announced in like December/January. Then more info in the spring. Then tickets on Sale in June/July for a fall fan fest and a Summer expansion release.

US Fan Fests
Year 1 was October 2014 - Heavensward was released June 2015
Year 2 was October 2016 - Stormblood was released June 2017
Year 3 was November 2018 - Shadowbringers was released July 2019
Year 4 was suppose to be November 2020 (then was Streaming only instead) - Endwalker was released December 2021
Year 5 was July 2023 which was adjusted due to the 2020 set backs - Dawntrail was released July 2024