Fifth summer doing this. Every year my traffic falls off a cliff around mid-June and every year I briefly believe I've been penalised. I haven't. It's just summer.
My rough approach now: June is for building the Q4 backlog, July I start seeding back-to-school and early autumn, August I'm already publishing holiday. By the time the busy stretch arrives the work is done and I'm coasting. Curious how others use the quiet months.