Are these allowed?
I have lots of posters from Scarborough Penthouse in the 1970s which were printed and displayed monthly, showing which bands were scheduled for that month.
Yeah, I think those are welcome. Set the date to just the month and list each band as a subject.
Yes, these are not all that uncommon. Many 1960s posters would cover a weekend of shows (or more) at venues like the Fillmore West or Winterland. Some times this was the same headliner, other times it was a full bill of other peformers.
Many clubs and even amphitheatres and arenas have done similar advertising since. kalli has the right idea though - set the date to the month instead of a specific day and add all the various bands as subjects. If you want to get specific, notate the headliner band for each date as such and the others as supporting acts.
Yep, sorted with these now, thanks.