Passing a knot on a fixed line can be a pain if you're not ready for it. A Gri Gri makes life easy.

1. Stop about a foot above the knot.
2. Clip a locker to the loop of the knot. If there is no loop, or if the loop is significantly damaged, tie a new overhand on a bight knot just below the first knot, and clip to that.
3. Put a Tibloc (or friction hitch of your choice) on the fixed line above the Gri Gri, and clip a double length sling (120cm) to the Tibloc.
4. Stand on this sling, this unweights the Gri Gri.
5. Remove the Gri Gri.
6. Sit on the locker.
7. Reload the Gri Gri below all the knots.
8. Stand on the sling foot loop again, and unclip the locker that is connected to the knot.
9. Sit on the Gri Gri, clean the Tibloc, descend.