Missing a day would mean you miss that day, and it cannot be compensated by riding twice the next day. Don’t stop your Tour de 100 riding streak if you do miss a few days here or there due to an unavoidable situation, like injury, or travel. Of course, with injuries, you have to take precaution before restarting, and advice of doctor as necessary.

Missing a few days here and there does not disqualify you from Tour de 100.