This is a pretty simple question, but I want to verify before spending a lot of time planning flights. Looking at UA's timetable, it looks like LAX-IAD-LHR on UA 924 gives 5448 miles. If I book this trip using different flight numbers (or 2 separate PNRs), I assume I would get the real mileage (5955 = 2285 LAX-IAD + 3670 IAD-LHR). Is this correct? I haven't checked the fare differences yet - this question is just about mileage.