Jim,
I believe the uniforms in question were of a hue which is today commonly termed "baby blue" and not of the darker English cloth. I have read that the troops were not too fond of these uniforms and that the clothing was a source of embarrasment for them. It seems however that this was all that was available to Longstreet's troops in East Tennessee during their sojourn there. If I am not mistaken no time was lost replacing them once the troops rejoined the bulk of Lee's army.
Len