This is what I can see after checking all my characters post-maintenance without doing soulboost related content:
SIN: 49 > 50
GUN: 53 > 54
KFM: 53 > 61
BD: 46 > 49
WL: 47 > 52
DES: 46 > 50
WD: 44 > 47
BM: 46 > 50
SUM: 43 > 45
ARC: 43 > 45
FM: 46 > 49
SF: 46 > 47
AST: 45 > 47
DB: 44 > 47
Not sure why some are barely getting any levels (SIN, GUN, SF for example) while most are getting the correct amount.