Originally Posted by UK flyer
Yes, you are correct. Because you are departing from T1 you will have no access to T4 departures. I would use the Arrivals lounge then the Terraces in T1. But that's a very long wait for a connection at the airport and I wouldn't fancy spending 9hrs in a lounge. If you don't have much hand luggage and your luggage is through-checked already why not make the most of the day and see London?
Heathrow Express connects T4 with T123 every 15 mins, free of charge, landside.
They are not BA Gold, but they are traveling First connecting to CE. They might really not want to go into the city for 3 to 4 hours as they have visited London several times. They will through check-in their hold luggage and will have very light hand luggage. I don't know why I got the impression the HEX was not operating out of T4 since January because of T5 construction. So if they go landside and use the arrivals lounge, they can take the HEX to T1 at 1 PM, can they use the First lounge there or will they need to use terraces because their connecting flight is in CE?