If the source SVM existed offline volume in the SVM-DR relationship, the update progress will be slowly, it's expected behavior, because the snapmirror will try to update for the offline volume, if the trying failed, the main relationship will be finished.
svm95dr1: XDP svm95dr2: Snapmirrored
Transferring 2.30KB true -
Idle - true -
Transferring 0B true 03/15 15:02:06
Volume voldr3 is offline, main relationship will keep waiting for the volume voldr3 until it fails.