My colleague Paul Riegler's recent review of the Delta Arrivals lounge in Frequent Business Traveler might be helpful to others who come across this thread.
Delta Air Lines Arrivals Lounge London Heathrow – Review
Delta now offers passengers arriving in London an arrivals lounge befitting the level of service it offers in Delta One. With the relocation of multiple U.S.-origin flights from Terminal 4 to Terminal 3 as part of its partnership with Virgin Atlantic (which also uses Terminal 3 and has its Upper Class Clubhouse – which Jonathan Spira reviewed in April 2014 – for outbound passengers) Delta opted to open its own arrivals lounge and took over the space previously used by Air Canada before that carrier’s move to Terminal 2.
Delta flights from Boston, Los Angeles, Newark, and New York now arrive at T3 giving passengers on those flights easy access to the lounge, while flights from Atlanta, Detroit, Minneapolis, Philadelphia, and Seattle continue to arrive at Terminal 4. Since the Arrivals Lounge is airside, it is possible for those arriving at Terminal 4 to use the Heathrow Connect train upon arrival and access the lounge.
Arriving on a flight from John F. Kennedy International Airport, I headed to the new lounge, which requires going outside towards the bus stops and making a left. Signage is good if you don’t happen to know where the old Air Canada facility was and the walkway is covered in case of inclement weather that is so often the case in London....
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