Why 10 days now? Whatever happened to a 14 day incubation period for the virus?

Slavyanka just returned from Europe, unvaccinated. Negative covid test 3 days before arrival. Negative covid test upon arrival. 14 day quarantine at home with another test at 8 days (which will be negative, too).

They just keep changing the goalposts and wonder why people aren't buying their crap.