Unfortunately you can't get into the BA Arrivals lounge off a domestic flight unless you are a BA or QF top tier elite. It is only for overseas arriving passengers in F and J on BA, or elites as noted. Even other oneworld Emeralds or Sapphires can't get in unless they've flown BA F or J from overseas. Also, it's in T4 and GLA flights arrive at T1. Thanks for reminding me about the inflation that has hit the Tube. I realize there is the 9:30 am restriction, but by the time one gets through the arrival process, it will be close to that time if they take the flight that arrives at 9 am. (Go have a good coffee in the terminal, then head into town.)