Airline tickets

Now is fine to start shopping, and purchase if you are happy with what you find

Each airline will have its own policy, so be sure to read the fine print

EDIT-- is this the trip to Scotland ( 13 day?) you planned for in 2020?
If so, look at 'multi-city' ( aka open jaw) routings ( e.g., PHX-GLA, EDI-PHX)

As Scotland is part of the UK, transiting through London, should not be the problem that doing so en-route to France has become for the time being.

Generally, you will pay more for a fully refundable ticket. You will need to decide on whether risk of cancellation is more important than initial price. If you have the ability to use frequent flyer miles, it is generally easier to get full refund with those. Read any cancellation policies before purchasing was good advice.

I'd also sacrifice some savings to fly as directly as you can to your destination city. I don't live near an international hub so I always have to have at least one flight to/from the hub.

What's on my mind is the new rule that is going into effect in France on Dec 18 where they are restricting tourist travel from the UK. There were a number of threads over the past few months from people who had booked on BA and were transiting thru Heathrow and worried about encountering issues for entry into the EU from UK. Those worries may have come to pass...or they may allow transits with no problem.

Just something to think about as you research. Which tour are you going on?

I'll also add that I am not particularly a budget traveler. I'm middle of the road and don't search for the lowest airfare, I want the most convenient routing on an airline of choice.

It's not too early to start shopping and comparing. I just bought nonrefundable tickets to Ireland for May-June, without change fees if plans fall through. I'm paying a little more to route through US connections than through Heathrow or other hubs, to avoid possible complications with Covid rules. There were plenty of available seats for my trip. I'll be buying insurance for the trip later.

I am going to a RS tour in September. After following airline tickets for months using hypothetical dates, I bought refundable open jaw tickets on United a month ago, PHX to LHR, VIE to PHX. It was the lowest price I had seen since probably a year ago, plus refundable. Things will change but I am happy with the price and the (current) connections.

As for refund policies, each airline has its own, so read their websites closely. I found United and Delta to be the easiest to understand and the least expensive refundable surcharge. Refundable is different than changeable. My tickets are for economy seats although I did pay for one seat preference.

Thank you all for your advice. After researching on various sites, I made my reservations today directly through the airline over the phone which was very satisfying. Ended up with a multi city deal, premium economy. Now I'm starting to feel like this may happen. Fingers crossed.