I don't see that this adds much. The best routes for the current Alphabet Challenge are easily turned into circular routes.
You can start at Aldgate and if your Victoria to Westminster train is going back to Aldgate you're sorted. Better still if you can choose to end at either Aldgate or Aldgate East.
Starting at a different letter, I suppose you could start at Canons Park to ease Dollis Hill and have a better alternative C at the end.
Also, this has to be the Alternative Alternative Alphabet Challenge because there's already an Alternative Alphabet Challenge.
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