Travel and logistics recommendations for Great Britain and Amsterdam

Can you arrange your itinerary so that you fly home from Amsterdam using an open jaw itinerary (in to one city, out of another booked on your airline website as multi-city or multi-destination)? Or go to Amsterdam first, then fly to Edinburgh and work your way down to your daughter?

Based on my research, all transportation from Oxford to Edinburgh (plane or train) will take us back through London.

Maybe not. I will be taking a train from Carlisle to Oxford in the spring, and the routes I found all took me through London, even though I would be backtracking. However, Stuart (isn31c) showed me that you can get a more direct route by buying 2 separate tickets. For example, in my case, I will get a ticket from Carlisle to Birmingham (which I would have to stop over at anyway) and then get a ticket from Birmingham that goes directly to Oxford.

Hopefully, isn31c will weigh in here and let you know if that's possible. In your case, you might have to get one ticket from Edinburgh to Birmingham, and then another for the Birmingham to Oxford route. And in my case, it's actually a bit cheaper to do it that way.

Pam - thank you for responding. Our plan is to bring our daughter with us when we visit Edinburgh and Amsterdam.

I too suggest you to look at an open jaw ticket; fly into London, fly back out of Amsterdam. This will make your trip much more easier.
With regards to where to stay in Amsterdam, it really depends on what you want to see and do and when exactly you will be visiting. April is absolute peak season for Amsterdam because of the tulips. It might be more convenient (and cheaper!) to stay somewhere else. In Haarlem or Leiden for instance.

Based on my research, all transportation from Oxford to Edinburgh
(plane or train) will take us back through London.

No, you can as mentioned take the train via Birmingham.

So, we will need to book flights from Edinburgh to Amsterdam and
Amsterdam to London. [...] Any recommendations?

From Amsterdam to London my recommendation is to take the train instead. Book in advance at www.eurostar.com

Easyjet flies from Bristol (BRS) Airport to Edinburgh. Do you need to go back to Oxford after visiting Bath?

Further to Mardee's post above her train from Carlisle to Birmingham will have started from either Glasgow or Edinburgh, as normally no Avanti trains start from Carlisle.

There is a broadly hourly service, at about 20 to each hour from Oxford, taking a bit under 6 hours. About the same time as going via London and having to change stations in London.

Looking at 11 December- one week's time Oxford- Birmingham is £24.40 on most trains (all run by Cross Country), Many trains Birmingham to Edinburgh (all run by Avanti) are £45 to £48, the teatime one at 1807, which I usually use (as far as Carlisle) is £29 from Birmingham to Edinburgh. I like that train- it is normally an 11 car service, so is not very crowded and has emptied out by Preston, so the last 2 hours there is lots of room.

If you leave Oxford on the 0939 or later get yourselves a Two Together Railcard for £30- it will save you 34% off the above fares.

I have a senior railcard and usually pay £12 on the 1807 from Birmingham to my local station in Cumbria (changing at Carlisle)- a 5 hour journey.

Looking at EDI-AMS flights next April fares on Easyjet are typically about £80 with your backpack in the bins.

On KLM, the route competitors, the comparable fare is £129.

Eurostar AMS to London St Pancras, for next April is priced at about £49 to £55 on most trains, booking today. Allowing for airport time Eurostar is as fast as flying, and I doubt you'll find a flight for that price.

I don't understand why your daughter can't return to Oxford from Amsterdam by herself. Easy to fly to London and train to Oxford. Have you discussed that option with her?