I’m BA Gold, and I regularly fly out of HND, most often on JL (and rarely in First!). I only recall ever being stopped once from using the Priority Lane (when on CX). Until reading this forum I didn’t really appreciate the rule (and didn’t argue when I was declined when flying on CX). Are they more flexible for JL customers?

I suppose there is little harm in trying to use the Priority Lane, and then if refused quickly move over to the regular lane.