There are 260 sleeps (260 days) until July 10 (Saturday, July 10, 2027).
There are 260 days until July 10 (Saturday, July 10, 2027) — one sleep per night.
One sleep per night between now and the big day — tonight is the first sleep, and the morning after the last sleep is July 10. Sleeps are the same as days.
260 sleeps is 37 weeks and 1 sleep.