The UK government released guidance at the end of last week to help aid amateur productions willing to return to the stage.
A large part of the new rules is based on the existing guidance released a number of weeks ago – which you can read about here. According to the new announcements, "professionals and non-professionals can now engage in singing, wind and brass in line with this guidance", though that for non-professionals "social interactions should be limited to a group of no more than two households (indoors and out) or up to six people from different households (if outdoors)."
As such, non-professionals meeting indoors and performing have to abide by the existing rules on meeting those outside your household. Shows featuring family members may be the most feasible solution given the present permissions. So don't expect any am-dram socially distanced versions of 42nd Street just yet.
The DCMS (Digital, Culture, Media and Sport department) is keen to emphasise that social distancing is still very much vital – "studies have also indicated that it is the cumulative aerosol transmission from both those performing in and attending events is likely to create risk", and as such as large amounts of care should be taken.
Furthermore, capacity should be maintained at a level that allows social distancing to be maintained, while venues will have to guarantee a high level of cleanliness to make sure they reduce the risk of transmission.
DCMS guidance reiterates that it is against the law for gatherings of more than 30 people to take place in private homes (including gardens and other outdoor spaces), though businesses and venues following COVID-19 Secure guidelines can host larger groups.