If you plan on STN being a possible diversion then you'd also not fancy just having LTN fuel on as there would be a lot of traffic heading there. So you might carry East Midlands fuel. You might well opt to carry fuel for a second 'good' alternate such as LPL so as to give yourself a choice come diversion time. That choice might have proved to be a welcome one if EMA was extremely busy at the time or had worse weather than STN. So you end up in LPL. Yes you pass some fine airports along the way but they don't have company handling and therefore will be difficult to get both the aircraft and the passengers out of.
Its a complicated scenario but thankfully these days we just push buttons and the computer tell us where to go and takes us there....
Cheers
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