Originally Posted by
flipperman75
...I was more thinking because of the continuing flight in Envoy, since the US website says Envoy tickets give Club access, but it doesn't really say whether it applies to the originating airport or just at the airport where you have the Envoy ticket.
The language of the main US website may be fuzzy, but
UK version of US website is clear that when flying Envoy, you'd have access to any US Club, the PHL Envoy Lounge, and any Envoy arrival lounges on your day of travel.