There are 256 sleeps (256 days) until July 6 (Tuesday, July 6, 2027).
There are 256 days until July 6 (Tuesday, July 6, 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 6. Sleeps are the same as days.
256 sleeps is 36 weeks and 4 sleeps.