Helen Beck, the line’s vice-president of international sales and marketing, said: "We appreciate some people are time-poor and don’t necessarily want even a 10-night cruise, so there are more seven-night sailings on [Crystal] Serenity in the Mediterranean this summer, for example. This is a new shift for us, so we will see how it goes."

She added the line was generally attracting younger people thanks to the more active lifestyle of Crystal’s yacht Esprit and its bulked-up river fleet, now numbering five following the delivery of Debussy and Ravel in quick succession.

It comes as the line also gears up for a revamp of the 1,000-passenger Serenity, which will arrive in the UK later this year after a three-week dry dock in October and November, with Beck promising ship visits for agents.

The work on Serenity will mirror changes already made on Crystal Symphony and will include 36 new Penthouses and two new Penthouse Suites, cutting capacity from 1,070 guests to 980.

Beck also asserted the company’s focus on the trade, following the line’s chief executive Tom Wolber’s announcement of a Crystal Partner Advisory Council, featuring 13 global big-hitter agent partners. Beck said they would provide “good counsel” for the line with UK agents on the council including Edwina Lonsdale, managing director of Mundy Cruising.

Elsewhere in its product range, Beck said Crystal Luxury Air – a Bombardier Global Express Jet XRS refurbished in February – is being used more by passengers to get further into experiential land programmes, such as spending three days in Burma.

The aircraft flies on-demand charter worldwide routes for up to 12 guests, featuring three cabins with flexible configurations. “It allows us to take guests to even smaller and unusual places,” said Beck. “It’s early days, but guests seem to be appreciating it.”

The line is also preparing for the arrival of its second ultra-luxury yacht, Crystal Endeavor, but Beck said it was too early to talk about the details of where it would sail in 2020.

The all-suite, Polar-class expedition yacht will be done “in Crystal’s way”, Beck said, such as including a heated closet outside guests’ suites for them to hang wet gear after excursions.