Originally Posted by BearX220

OK, do the simple thing and nail down the BOS-DUB-BOS award seats first. They're the anchor. Out June 21, back July 7.

You have much more flexibility on your DEN-BOS-DEN travel, especially on the return when you're laying over for a few days and not connecting. So let part of the itinerary float for awhile. It's early to book those domestic legs anyway, with miles OR cash.

And given that on June 21 EI136 BOS-DUB departs at 615p, I would think about flying into BOS the prior day anyway, or on a Friday night redeye if your wife has to work on the Friday. For a same-day connection through BOS on two different PNRs, I would advise a schedule arriving in BOS at least four hours prior to your Aer Lingus departure. It's difficult to depart DEN early enough on June 21 to land in BOS no later than 200p. In fact one of the few ways I see to do it is UA532 dp DEN 610a ar ORD930a, then UA532 dep ORD 1040a ar BOS 200p. (Yep, same flight number but two different segments, which could easily mean a change of aircraft at ORD, and the schedule could change a lot in the next nine months.)

At any rate a two-flight trip like DEN-ORD-BOS adds risk and worry (late ops, missed connections, missed baggage transfer, etc.) and all but the itin cited above get you to BOS too late, though many have UA saver award availability. If anything goes wrong on your Saturday (late / cancelled flight, weather / summer storms at ORD, etc.) your trip is shot.

If it were me I would book the EI transatlantic bit now, then stay loose re: the rest, but probably lean to an afternoon flight on Friday June 20 and an overnight stay at BOS (the airport Hyatt is quite nice), stress-free Saturday brunch in Quincy Market, and leisurely check-in / onward travel that afternoon and evening. For the final bit of your return trip, of course, you can do anything you want as you're planning a layover anyway.