Originally Posted by
corporate-wage-slave
I really wouldn't worry about this. I'm in CCR 3 or 4 days a week, and I can absolutely assure you that nearly half the people in CCR are in very similar situations to you, some going to Europe, some going further afield. Just keep your First boarding passes handy - it is not essential but it speeds things up.
If you arrive in First on BA metal on the same day (and in some cases the previous day) and then depart T5 on BA metal then you will be allowed in to CCR. There is no confusion on this point, though maybe some recent posts may have given you that impression, just see it as people trying to be as helpful as possible
Just to add apologise if I have confused matters. As noted by the lounge manual extract I posted BA don't distinguish between l/h->s/h or dom connections and l/h->l/h connections. BA seem to offer more than is simply provided under the oneworld model of lounge access during connecitons, so l/h->l/h connections arriving on F would allow access to the CCR.