I believe AAU1 and AAU2 were public beta tests in MSFS 2020, but AAU3 and 4 were not public beta tests.
Interesting to look back at the update history for the ATR:
- 2023-04-25 Original release notes for the ATR
- 2023-05-09 v1.0.8 (FSElite.net)
- 2023-06-21 v1.0.20 (FSElite.net)
- 2023-08-24 v1.0.31
- 2024-01 v1.0.36
- 2024-10-10 v1.0.46 (STOL 600 variants)
- 2024-10-24 v1.0.49
- 2025-12-04 notable for NOT getting updated with SU4 while 99 of 130+ first-party aircraft received a variety of updates
- 2026-04… AAU4 coming soon