Originally Posted by
Door5L
You might want to check this out carefully before risking it. I am not sure if the boarding card QR code, including on the app, has restricted validity (i.e they are not intended to be used as multiple entry for security reasons) and I am sure you would need to ask a BA or HAL member of staff to escort you back through arrivals, including possibly passport control. I think going airside is intended for those who are actually flying rather than to facilitate access to work in a BA lounge.
As far as I know all QR-codes from the airlines are one time use only at each stage of the process.
I have had to leave the departure lounge sometimes for various reasons at several airports (none of them have been British nor BA though). The gate won’t open and you’ll have to explain to the staff what you’re doing and they will note a deviation and you might have to identify yourself.
Two examples I did this was at ARN when I needed to move from one terminal to the other and the airside buses weren’t operating.
Another time I was scanned in by security in Madrid before they realized that my partner didn’t have fast track on her boarding card and I opted to go back out and go through regular security with her. That also included some paper work.