There are 270 sleeps (270 days) until July 20 (Tuesday, July 20, 2027).
There are 270 days until July 20 (Tuesday, July 20, 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 20. Sleeps are the same as days.
270 sleeps is 38 weeks and 4 sleeps.