Re: Booking BOS-DCA and seeing if you can route in an extra segment in there via standby/confirmed flight change.. I vaguely recall some discussion when free same-day confirmed flight change were announced for EXPs about not being able to change connection points? Or was it standby? (I'll have to see if I can dig up the language or perhaps I'm conflating different discussions.)
Depending on your time flexibility, I do think $65-$75/segment is doable, but if you're looking to do after work weekday runs, I think you're going to be limited to two segments (outbound/inbound) each night. If you're able to start mid-afternoon, you may be able to catch a 3-segment run for also about ~$135-150 RT. Do you think you have enough time? You mention 45 days before the end of the year, but with the high fares surrounding the holidays, I'd say you realistically have about 3 weeks where you can find cheap weekday or weekend fares. (Combination of personal experience and guessing - nothing scientfic
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