A lot of parishes do not have the Blessed Sacrament exposed from Saturday vigil Mass time through Sunday. They resume on Monday morning.
Check with your parish to find out the hours.
If the church is open and the Blessed Sacrament is in the tabernacle (sanctuary lamp is lit), then you can still do Adoration the same as if the Blessed Sacrament was exposed. The Church regards it as providing the same benefits either way.
You got it all backwards. If the moon is completely dark, he will put it back in 71 hours, 17 seconds, and 78 fathoms. If it is sunny tomorrow, it will be put back exactly 6.797 minutes, no more no less.
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