Crisis-management has always been part of a choreographer’s skillset, but staging a new ballet with two large alternating casts has rarely been fraught with so much risk. It was one hell of a week for Valentino Zucchetti, first soloist at the Royal Ballet and creator of Anemoi, the 20-minute work that opens the final programme in the company’s 90th birthday season.

People often ask why it is that in ballet there are different casts on different nights, a practice alien to opera, musicals and theatre. The most obvious reason is practical. Ballet companies keep a number of principal dancers on salary who need regularly to strut their stuff. Another reason is that dancers develop distinct individual qualities – technical, musical and dramatic – which imprint on the works they dance.

The Royal Opera House wasn't taking any chances when it welcomed its first ballet audience since December this week. There was no printed programme on offer, nor even a cast sheet. “Not till October” said the uniformed man on the door. Some ballet companies have learnt the hard way not to trust that newly lifted lockdowns (lockups?) will stay that way for long. They’re in no hurry to spend time and money on printed material that might end up having to be pulped.

Like the British high street, the once richly diverse landscape of dance in the UK is likely to look very different once lockdown is fully lifted. There will be losses, noticeably among the smaller companies whose survival was always precarious. There will be downsizings. There will be painful gaps where a major talent has given up the fight, retired to run a flower shop or become a hill farmer. It will take years for the sector to recover.

Unfazed by yet another forced cancellation, the Royal Ballet has notched up a small triumph over the virus. When what was to have been a performance to a live audience in the Opera House fell prey to new restrictions, it went ahead anyway.

"Don’t hold back,” a front-of-house manager told us. “If you want to show your appreciation, go for it.” This was nothing to do with providing sound effects for the imminent streaming to tens of thousands around the world. It was about letting the performers know there was a real, live audience in the House.

Vintage champagne was served up last night, and whether you found the glass half-full or half-empty would depend on your perspective.

“That’s Marcelino Sambé, he’s wonderful,” said the artistic administrator of the Royal Ballet as I followed her down one of the many corridors that weave throughout the Royal Opera House in Covent Garden. “He’s a newly promoted Principal, a very special talent indeed!” I looked over my shoulder at the figure disappearing through some doors.

The cello is the stringed instrument most closely aligned to the human voice. It has a human shape, too, so in theory it was a short step for choreographer Cathy Marston to give it a living, breathing presence in her ballet about the legendary cellist Jacqueline du Pré. But what a giant leap of imagination that turned out to be.

It’s no surprise that audiences love John Cranko’s Onegin, with its vividly economical narrative (close to Tchaikovsky’s opera), attractive decors by Jürgen Rose, and intelligent drama. True, it feels a tad old-fashioned – although that, as my neighbour observed, is part of the charm. Performers love it too, for the meaty roles it gives to its principals and the emotional swoop of their dances.