Organisers of the BBC Proms are having to be flexible in response to "constantly changing regulations".
Conductor Sakari Oramo has revealed organisers are creating multiple programmes for every concert amid ongoing concerns relating to the coronavirus pandemic.
Oramo told the BBC: "We're dealing with constantly changing regulations.
"The advice on how many players we can have, whether we can have singers, whether there are restrictions to certain sections like the wind or brass, has all been - to put it mildly - slightly unclear.
"I completely understand it. I don't find it strange that there's a lot of uncertainty going on. But of course the number of players we can have, and the distances we need to have between players, will affect the programme greatly."
Oramo admitted that in spite of the best efforts of organisers, this year's event is likely to lack its usual atmosphere.
At present, it appears unlikely that audiences will be allowed into the Royal Albert Hall to attend the Proms in person - but the performances will still be broadcast on radio, TV and the BBC's iPlayer.
The conductor said: "There won't be a Proms atmosphere in the same way. But, of course, once the music gets going, the music will take us where it needs to take us.
"I'm sure the first night will be an especially important moment, not only for the orchestra but also for the whole music-loving nation, and the world."
Oramo also revealed he plans to create a performance that reflects the chaos caused by the pandemic.
He shared: "We've gone through a list of pieces that are suitable to that purpose. But obviously as well as reflection, there needs to be something uplifting.
"So I hope the final result will include those two opposite fields of energy: quiet reflection and mourning from one side, then positive energy and optimism on the other."