Breaking up flight time from seattle to ljublana

I typically do this- to see somewhere else, but also, it gives you the opportunity to acclimate to the time change so you're ready by the tour. And- I also wouldn't fly to your tour starting destination the day of the meeting dinner, in case of unanticipated delays.
Last time I took the train from Munich - Salzburg (flew into Munich 2 days prior) for the start of the Alps tour. But then- train delays! I was glad I started early.
You could book one night in the tour hotel and spend the day before the group meeting seeing sights in the city the tour won't cover.
And sometimes I go somewhere, after the tour!
I seem lately to always end up connecting through Amsterdam from SEA, London is a great choice. For something totally different, Iceland Air has "stopovers". It's great to have so many options!

Hi, for my flights to the Adriatic tour two years ago, I did fly to London, and on the way home from Dubrovnik I stopped overnight at Schiphol, staying at Leiden. This is what I did. Delta flights were all booked on one reservation multi-city ticket.

Delta: Spokane to Seattle to London.

(My husband & I stayed in England & Wales for two weeks.)

Easy Jet: London to Ljubljana.
Adriatic Tour
Easy Jet: Dubrovnik to Amsterdam.

Overnight in Leiden

Delta: Amsterdam to Seattle to Spokane.

Important tip: I didn’t try to fly two different airlines on one day. If there’s a hiccup with the first airline, you wouldn’t want to be stuck unable to use your Delta flight back home.

If you have the time, why not make the most of the traveling to get to Europe?

It can get you a better flight schedule also, since once you're somewhere in
Europe, you most likely have more connection options.

This approach also works on the return, although the anticipation factor may be
less after the core trip has completed. But it can be a good way to position for
the transatlantic return flight - you don't have to get up at the crack of dawn to
make a connection from, say, DBV to FRA.

You can sometimes get intra-Europe flights for a small # of FF miles, like, less than
10k.

I would slightly amend Jean's comment to say - don't plan to fly two flights booked
on separate tickets in the same day. You can always have a hiccup on the first
flight, but as long as the second flight is on the same ticket, the airline is obligated
to get you to your final destination.

If you want to visit another destination, great! If it is just about the flight time, I hardly think it is worth it. Once you have made the flight to Europe from Seattle, the next connection really doesn’t feel that bad or take too long.

I spent my extra days in Ljubljana before the tour and was glad for the extra time.

I guess I am doing something similar for my next RS tour. It begins in Prague. I will fly to Rome and attend the Assisi 4-day festival, plus a few other Umbria cities. Then I fly to Prague, spend a couple of days in Cesky Krumlov, and meet up with the tour group in Prague. When the tour ends in Budapest, I may spend a day or two near Amsterdam before flying back home.

I agree with Carol. If you’re doing this solely to break up the flight time, then I wouldn’t bother stopping at London. Even with my extra flight compared to yours since I begin at Spokane, I will take multiple flights and even a train to reach a beginning destination vs. stopping midway to have less transportation time on that travel day. And I’m in my late 60’s, if that matters.

Since you can't fly directly to Ljubljana, it makes sense to get yourself over and back in whatever way makes the most sense to you. There was just a post about the cities you can fly to direct from Seattle. They are: Reykjavik, Dublin, London, Paris, Amsterdam, Barcelona, Copenhagen, Frankfurt, Zurich, Rome, Istanbul and Helsinki.
Of those, there are direct flights to Ljubljana from London, Paris, Amsterdam, Copenhagen, Frankfurt, Zurich, Istanbul and Helsinki (according to directflights.com).
Tour ends in Dubrovnik, which has direct flights to London, Paris, Frankfurt, Dublin, Rome, Amsterdam, Zurich, Helsinki, Istanbul and Barcelona.
These intra-European flights are generally very inexpensive and could be substituted with a train journey (e.g., overnight train from Zurich, https://www.seat61.com/international-trains/trains-from-Switzerland.htm#Switzerland-Croatia).
If you fly in one day and out again a few days later, you don't have to worry about separate tickets or delays or whatever.
And you don't have to fly into and out of the same city. You can either buy two one-way tickets (or a total of four one-way tickets) or an "open jaws" or multi-city ticket. Play around with your calendar and skyscanner.com or google flights to figure out what makes the most sense for you.

Thank you all so much for the great info! This will help in my decision making immensely!

We are also west coasters. Our plan is to fly to Venice, adjust to jet lag there for a few days, and then bus to Ljubljana. (It appears to be an easy and comfortable option.) For us, we'd rather skip going to another airport. Just another option, depending on your style of travel, and where you'd like to spend your time.

If you have the time, I'd break it up. I always do. London is my preferred stop as I take the day flight. Lots of times I just stay overnight, but other times I stay longer, as London is a great city. Coming from Seattle, I'd have to break up that trip and I would recommend a city near the coast to limit your on flight time. Any further into Europe and you defeat the purpose of shortening your flight. IMO. I'm spoiled being on the east coast. My preferred limit on one flight is 7 hours. Did 9 hours once and thought I'd go stir crazy. LOL.

Personally I'd fly direct into either Frankfurt or Zurich. And check what your costs are because a flight from either of those locations in May should be around $100. It's just as fast to fly to either of those major cities from Seattle as it would be to London. And with London you would then have another time change enroute to Slovenia. Better to get as far east as you can inside of a 10 hour flight radius.

I definitely feel better informed and less anxious!
Thank you so much!

Headed out on this tour next month. Flying from Seattle to Zagreb (explored lots of options and multiple airlines but best pricing and schedule on British Air with 3 hour layover at Heathrow) then doing GoOpti shuttle two days later to Ljubljana. Rental car one way was too expensive. Doing food tour, walking tour and wine tasting in Zagreb. Picking up rental car in LJU to see more of Bled region than tour does and to see the caves south of LJU returning in time for tour to start. Flying from Dubrovnik to London to Seattle after a few extra days at the end of the tour.