If, like me, some of your travel seems to be sponsored by lastminute.com, OLCI offers an occasionally useful 10 minute window.

When heading North at the end of the week, I tend to leave myself just enough time to make the airport. Ocasionally, traffic on the Marylebone Road makes me miss my target Hex and in the old T1 days, that could mean getting to security 20 minutes before scheduled departure time. Then again, in the old T1, domestics never took off on time.

The T5 35 minute conformance window has made me take one Hex earlier than I used to, but on a couple of occasions, I've left it late and got to conformance with just a few minutes to spare.

Check-in closes at T-45 whilst conformance is T-35, so for me at least, one of the benefits of OLCI is that I do have that extra 10 minute window to deal with unforseen delays.