Government test or self test? If the latter, I wouldn't report it, because you and your entire crew could be quarantined. If the others tested negative, let them depart as originally planned. Re-test as George recommends, in case you had a false positive. Then look for accommodation and self-test until you get a negative.

The numbers have spiked and super spreader events have not been cancelled. I'm guessing, between increased testing, potentially affected health care care workers, and three days holiday, the government will struggle to do timely retests.