Originally Posted by
trekker
but unless UK carry-on allowances have changed, we will have checked bags
Also, what do you mean by this? The UK allowances, at least at LHR, are pretty similar to everywhere else...1 normal sized roller carry-on and 1 personal item, briefcase, etc. They're definitely strict about carry-on size when you're departing T5, but I never had any issues at the T3 connections security check where you'll be passing through.