We always have a Milepost with us when on the road here. We tend to avoid commercial campgrounds in favor of the provincial and territorial campgrounds. We also like quiet places to pull-off and relax in isolation. And for this, the Milepost is irreplaceable. It provides info about every side road and abandoned location/site that can potentially make for a good campspot.
The Milepost lets you know about wildlife viewing opportunities. It lists the good fishing spots. They check for planned road construction. There's historical information in it too.
The Milepost is updated via their staff who travel the highways the season before. So, they were touring last summer for this year's Milepost. They ask businesses about heir plans, but often those change for a wide variety of reasons.
For instance, one lodge where we always fueled up was magically closed with no notice whatsoever a few summers ago. Turned out there were some business management issues.
Another time, a place that was listed as closed had new owners and was open.
The Milepost is a good guide and is as up-to-date as possible. For more up-to-date info, check in at the Visitor Centers in Yukon. Although, one year a handout they were giving was wrong too. It happens.
I have a 1966 Milepost that was saved by my parents. It's fun to read too.