England extension cancelled

I'm signed up for September Mediterranean cruise. My friends had signed for the extension to England. Found out today that Viking has cancelled that extension. My friends are holding airline tickets from London to home. They used points and did not buy airline from Viking. I'm wondering how Viking will handle that as my friends will either have to fly to London on their own at the end of the cruise or need to change their tickets to fly home from the final cruise destination. Either way I'm sure it will cost them money. Wondering why Viking cancelled this extension. Haven't seen it on their website for more than a year as an option. Was this cancellation just this one portion of the itinerary or will they cancel it for all extensions to England? Just wondering outloud.