The Snowsports Trail/Piste is lacking options for marking snowbiking. Probably for the obvious reason that mountainbikes already have extensive tagging options. But not for separate winter trails. Winter trail biking has only started to grow in the past few years so a fairly new phenomena. Many places now have dedicated winter biking trails when that wasn’t happening just a couple years ago. And private people have either some kind of method for creating winter trails or snowdogs. So it’s rapidly becoming common instead of very rare.
So either a bike option in the Type field or in the grooming field or both.
Also the reverse would be useful of having an extra option for normal path feature to have an option to indicate that it stays open during the winter as well.