CSE3520 - How the conditions are to be interpreted: Number of members and memberships: What are “qualifying supplies”?
You should check the other guidance available on ֱ from HMRC as Brexit updates to those pages are being prioritised before manuals.
‘Qualifying supplies’ are services which are ‘directly necessary’ (see CSE3720) to enable a member of the CSG to engage in the exempt and/or non-business activity for which the services are supplied.
Revenue and Customs Brief 10 (2018) explains HMRC’s revised approach to the test for directly necessary services.