Last night I was capturing and infecting low level Pokemon to give away on Wonder Trade.
I was using an infected Hypno as an infection source, this Hypno contracted Pokerus 3 days ago (and decremented its counter to 1 by being on the party on the date roll over)
When doing the wonder trades the clock hit the 00:00, and newly infected Pokemon were suddenly cured, even when they where just infected a few minutes prior.
The thing that puzzles me its that i was playing Pokemon Moon so the day reset should have been on at noon not at midnight (as mentioned on When does Pokérus in Pokemon Moon have a chance of being cured: midnight game time or midnight system time?)
So, is this a glitch, or are the "days to cure" inheritable? The entries on Bulbapedia an Serebii don't mention this at all