It depends how you do them. We've settled on a particular pattern: the bookends are done separately HBO (in fact, often with nothing in hand other than the passport) there-and-back to easy immediate turnaround destinations, usually AMS. So it's 2 x OLCI and BP prints, 2 x security, 2 x 3-hour trips each including about 20 minutes of plane-watching at AMS. Usually done at the end of a working day when a complimentary glass of champagne after bunking off early is very welcome, and we're still home by 8.30 pm.