Hi @Ben_Efrati, I checked the table source file documentation and there is nothing there that leaves out FLOW_INIT, however, I believe that's an oversight given the details on the FLOW_INIT event:
Thiseventis triggered (once for TCP and unique UDP/IP flows) after packet filters, but before any AFM and TMM work occurs. The use cases for this event are:
Override ACL action
Bandwidth control on both client/server flows
Routing to another Vip
Marking qos tos/dscp on both client/server flows
I confirmed in my own local test that I am seeing the same behavior as you. You could open a case to get official confirmation, but I'm pretty confident you'll need to perform your lookups in CLIENT_ACCEPTED or later.