Quote: "
SOE
Why do you say arriving in LHR T5 allows you to pass through security but not immigration ? I arrived BA from Hamburg and nearly missed my onward to GLA because flight connections DID take me through 2 dedicated immigration lines, neither of which was for EU passports and both of which were jammed by some non EU passport holder requiring 15 minutes of attention at the head of the line. UKBA ''service'' ?? Only made the GLA flight because it was half an hour late boarding. Such are the joys of LHR, even with BA straight through ticketing"
It may be the difference between an international-international transfer, as described by SOE, and an international-domestic one, where border control takes place at LHR and baggage claim/customs at the final (domestic) destination, provided that luggage is checked through.
AFAIK, this is standard procedure in most countries where luggage can be checked through.
Obviously domestic-international and domestic-domestic would be unaffected by all this.