1. Yes it will give you a warning in the dash central display.
2. Were you able to clear the code? if so, see does it come back after a few days. It doesn't sound serious as it hasnt thrown a CEL and is only intermittent. Was there a counter reference on how many times the fault was logged? Worth mentioning to the dealer when in for service, especially as still under warranty. Also, as yours is a 2018, has it had the haldex unit serviced. id get that done, and make sure they clean the gauze filter also. Theres plenty of threads on the subject on here.