I'm not in the family sponsorship category, i was accepted on H&C and they requested the ARC when i was approved.
It took a year to grant me the ARC coz it was refused first time and i appealed and i have an interview and then approved which took a year for the whole process.
Once your sponsorship is approved, they will request the ARC application from you.
It sure takes a long time and you can just hope for the best, some members took them weeks to be approved and others years so it really varies from a case to another.