I haven't added any Shubunkins to my small pond for two months now, but the last two I introduced didn't come out of hiding for about two weeks. I think part of that is because they were only two inches long, much smaller than the rest of the Shubunkins.
My pond is heavely planted with both water lilies and bog plants. I feel that I have a good balance of plants in my pond that provide good cover for the fish that are a little more skidisih than the rest.
For the most part, they all go into a feeding frenzy when I feed them.