Tannins From New Cedar Bleeding Onto Wall

I am in Seattle and just had a new fence built from clear cedar. The fence is in partial shade. Most of the fence was built about three months ago while other parts are relatively new, built in the last week. I have bought Restore-A-Deck "natural" semi-transparent stain and was hoping to have my staining contractor do the job this month, but we are now in the rainy season in Seattle, so that may be wishful thinking. 

We've run into a problem, however. The fence is built directly on top of a concrete wall. That wall was recently stuccoed with a very light stucco color. Soon after the stucco was applied, and as soon as it rained, we noticed that the stucco was showing discolored stains, like something had been spilled over the edge of the wall and then dried on it. I'm including a photo. Even before the stucco was applied, there were stains bleeding down from the wall onto the concrete, but because it was gray concrete, I didn't think that much of it. 

I'm pretty sure this staining of the stucco wall is occurring because of tannins bleeding out of the cedar when it becomes wet. I have several questions:

1) Does this look like the problem is one of tannins bleeding from the wood?

2) Will this bleeding stop of its own accord at some point during the next 6-9 months?

3) Should I wait until next spring or summer before attempting to apply the RAD stain? (I might not have a choice in light of the weather.)

4) Would the RAD semi-transparent stain "seal in" the tannins, such that the bleeding would stop? (I assume the stain would repel water, and so that might stop the cause of the bleeding?)

5) Should I use RAD cleaner and/or brightener before applying the stain? 

6) Do you have any other suggestions or ideas for products or techniques that would help in dealing with this problem?

Thank you for any help!