This is a regression we are already tracking.
Right now, SIMCONNECT_OBJECT_ID_USER corresponds to aircraft when you are in the cockpit and avatar when you exit the aircraft.
We plan to address this by splitting this into:
SIMCONNECT_OBJECT_ID_USER(=0): legacy value for user aircraft ObjectID
SIMCONNECT_OBJECT_ID_USER_AIRCRAFT(=0): value for user aircraft ObjectID
SIMCONNECT_OBJECT_ID_USER_AVATAR: value for user avatar ObjectID
SIMCONNECT_OBJECT_ID_USER_CURRENT: value for user aircraft/avatar ObjectID (current behavior of SIMCONNECT_OBJECT_ID_USER)
This will be part of the next update.
Regards,
Sylvain