How frustrating and completely understand the annoyance after a long flight.

It is absurd to me that generally in T5 you have to find your way to the lounge for any substantive help (on a transfer).

Also, the three recent irrops I've had requiring rebooking from LH to SH, never has a CSD told me on the fly in F, and in 2 out of 3 instances I've had to get my new bookings myself from the appropriate desk and I am GGL/CCR. But just presume that's how BA treats everyone from valued customers to first timers.