mnbp

Looks to me like DL is transitioning this route to less-than-daily operation, and your booked date might no longer operate as a non-stop flight.

Every Saturday is "schedule change Saturday", and as the previous poster advised, wait until tomorrow to see what happens.

Whatever automatically happens to your booking, if your booked non-stop flight is canceled, you have a "golden ticket" where you can choose to cancel or rebook your flight for no fee for any reasonable itinerary you might choose.

For example, if you still wish to travel on a day where your non-stop was canceled, you could propose to a DL phone agent that you'd like to extend your trip by a day because a connecting itinerary might have given you a shorter London visit. Or, if you prefer the non-stops, you could propose to the phone agent adjusting the travel days of your itinerary to maintain non-stop flights in both directions.

Once the schedule change dust settles and if it does turn out that one of your booked non-stop flights is no longer non-stop, take a look at the available flight options (disregarding any price difference) and decide what you'd prefer - even if on different days. DL will gladly move you to your preferred choice for no charge whatsoever. If the first agent doesn't readily agree to fix your booking as you prefer free of charge, politely say "Thank you, I need some more time to think about my options." and call back later.