I am not certain about the dolly or "bully" fishing, but with this recent rain, the winter brats that were waiting at the mouth of the Cascade are now going to be up in the Cascade and very fishable here shortly.
I personally do not bank fish the Cascade, I boat the Skagit, but I know several people that do. It will be go time in there VERY soon.
If this rain can hold off the fishing in the Cascade, Skagit and the Sauk will only get better from here on out.
Probably not directly answering your question, as I do not specifically know regarding the bullies. My guess is that there are still going to be so many chum carcasses in the river, it will be good for quite some time.