It looks as though you're all set with a good training plan and have heard about the resources, tips, tons of info on the Cascade Bicycle Club's site too.

There are also at least a few archived threads on the Northwest forum here on TE, that are "STP-specific", as a number of TE women have posted for information from those of us who live in the area and who are STP veterans, so I'd suggest searching through and reading all of the helpful information that we've shared over the years.

Be sure to incorporate group rides - even with a few others - into your STP training, as you'll want to be prepared to ride with @ 9000 of your fellow riders on the STP route, complete with traffic, RR tracks, lots of pacelines, newby riders and too many personal SAG vehicles adding to the crowded route - ARRRGGGHH!

Tailwinds!
Mary