I know the showmakers don't tell the time in Game of Thrones, but I believe an estimate can be done on how long it would take for all their travels.
So from the day Theon/Reek and Sansa Stark (Sansa Lannister? Sansa Bolton?) escape the Boltons, to the day of the Battle of the Bastards, how long has it passed?
There are accurate maps of westeros in the web, and the average miles per day of their choice of transportation is also well-known.
It is not concerned with whether the timelines shown are simultaneous or not. Focus only on the Starks movements in the North.