Booked a BA Coded and ticketed return trip from Glasgow to Dublin operated by Aer Lingus and have a BA Gold Card. Access to the lounge in Glasgow was no problem. Now that I am on my way back to Glasgow I've been denied access to the T2 and T1 lounge. When I checked in online for the return leg (DUB > GLA) BA diverted me to the Aer Lingus website for check-in and I was issued an Aer Lingus mobile boarding pass. None of the lounges would accept it and the lady in the Aer Lingus lounge at T2 was a bit rude and cheeky about it, told me that even if she was going to let me in, I can only use the lounge if flying to LGW or LHR. Tried the lounge in T1 and the lady there was more helpful but she said since I don't have a BA issued boarding pass she can't let me in. Advised me to get a BA issued boarding pass next time and I would be fine. Had I known I wasn't getting access to lounges, I would have stayed airside at my airport hotel for a bit longer. Hope this helps others.