Bearing in mind that CV 19 may make this a non issue...
DS (4.5) is off to school in Sept and has 5th birthday in Oct. Reception and Yr 1 share a classroom and depending on ability, can be quite mixed for lessons, so potential for friends in both years. So if I can do a birthday party in October, will a whole class party (which could be up tp 30 children) be expected? Or would it be reasonable to stick with X amount of friends?
If it's a whole class party it will be village hall/party games/cake and jelly sort of thing.