Just thinking of other Scottish clubs I go to: 2 of them continue all year round. One is monthly, and does not have guest nights in July and August, just session nights. Another is weekly, with guest nights once a month and sessions the other weeks, but again, no guests in July/August. But at least, they keep going.
One other club nominally takes a July/August break from monthly guest nights, but has in the last 2 or 3 years been asked by bands if they can come and do a gig for us in July or August. After due deliberation, it was agreed that they could do it in our usual premises but under a diferent set of conditions than the usual ones, with them shouldering more overall responsibility than the club committee. These "extra" gigs have proved popular, with reasonably good attendances.
Of course, in Scotland, summer holidays start a month earlier than in England, but there are enough of us grandparents, not taking our holidays then, to fill the seats.
And we also have a plethora of festivals, from March to October mainly, but not forgetting Celtic Connections and the Burns bonanzas in January!