There was no sheltering in the Blue Ridge, Jackson was going after Milroy, since Fremont dispatched them to Staunton, Jackson ordered Ewell to cross the Blue Ridge at Conrad's Store and take his (Jackson's) position on Bank's flank at Harrisonburg. Jackson and Johnson would combine, defeat Milroy and then quickly turn to defeat Banks, with Ewell.
There were two valleys, Luray and Shenandoah, separated by the Blue Ridge; Jackson with the help of his cartographer, Hotchkiss utilized each to maneuver shielded from the enemy.
In fact Banks reported on 4/28-"Our force is entirely secure here. The enemy is in no condition for offensive movements...I think we are now just in condition to do all you can desire of us in the valley....." Two days later he reported "Jackson is bound for Richmond. This is the fact, I have no doubt" Just how wrong he was would have disastrous results.......