Originally Posted by
cosmo74
Sorry, I'm a bit confused - I'm a GCH and in the same situation as the OP, arriving in J on BA, then transferring to BA Comair on a separate ticket in Y to CPT. I'm hoping the international J boarding pass gets us into the lounge ...
Your BA Gold will get you into the SLOW lounge if you're flying BA domestic operated by Comair. It's exactly as you would expect, and utterly conventional. You would get entry even if your JNB-CPT in Y was the only flight you were doing, just as you'd get into GF if flying LHR-EDI.
The SLOW lounge may in some circumstances allow you entry, even if you are flying some other airline, but that's really not relevant to your situation.