I know I caused confusion about going around T3 and T5. I'd read about shopping at Heathrow so in my mind the airport was like a giant mall with concourses and gates. I now understand that's not the case.
And I thought a spa might be another option for time at Heathrow. This is from an article in Travel + Leisure:
"Airport Spas Are Taking Pampering to New Heights
In fact, many of the latest airport wellness efforts have been championed by airlines—see, for example, the beauty bars at Delta’s Centurion Lounges (in San Francisco, Vegas, New York LaGuardia, and Dallas), the British Airways’-led Elemis Skincare-branded spa at London Heathrow Terminal 5, or the ultra-lush Aurora Spa in Qantas’ First Class terminal at Sydney International."
I had a day in 2014 in PHL. I was able to get from domestic to international and pretty much go all over the airport with my boarding pass. It was a crazy mixed up day and I ended up coming right back to MI that afternoon.
I think we experienced something similar in MIA and ATL. Our gate was on one end of the airport but we were able to visit all concourses for shopping and eating.
Is it the difference of our US airports with Concourses as opposed to Heathrow with Terminals?