There are 140 sleeps (140 days) until March 12 (Friday, March 12, 2027).
There are 140 days until March 12 (Friday, March 12, 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 March 12. Sleeps are the same as days.
140 sleeps is 20 weeks.