Hunters Mark seems to carry over between combat. I killed something a while ago which ended combat. In new combat later on I was able to use it's re-apply option. Not familiar with it in DnD, only googled the 5e description. Could be intentional in the game. https://www.twitch.tv/videos/762487605?t=3h22m10s
Hunters mark lasts 8 hours and can be re-applied during that whole duration (D&D 5e rule)
