According to the chart in the OP, they just changed it to "Mixed Amateur." And I'm wondering if that's a move trying to head off legal issues arising in the wake of upcoming rule changes regarding eligibility to play women's divisions.
All significant changes to class names and division names/codes:
2007 and before the Classes were Pro Men, Pro Women, Amateur Men, Amateur Women (MP, FP, MA, FW)
2008 they changed to Pro, Pro Women, Amateur, Amateur Women (MP, FP, MA, FW)
2012 they changed to Pro, Pro Women, Amateur, Amateur Women (MP, FP, MA, FA)
2018 they changed to Pro Mixed, Pro Women-Only, Amateur Mixed, Amateur Women-Only (MP, FP, MA, FA)
2023 they change to Mixed Pro, Women-Only Pro, Mixed Amateur, Women-Only Amateur (MP, FP, MA, FA)
2018 also changed the "Masters (MPM, MM1)" "Grandmasters (MPG, MG1)" etc to age brackets "Master 40+ (MP40, MA40)" "Master 50+ (MP50, MA50)" etc