Hey Brad,
Done the Bidwell section a fair bit in the 90's and early 2000's. I've always did it in Sept., lots of eagles and bears when a salmon run is happening. The video's posted above, doesn't do the Chilko justice, it's at a very low level. Here's a link to the Chilko gauge -http://wateroffice.ec.gc.ca/report/report_e.html?type=realTime&stn=08MA002&dataType=Real-Time&startDate=2015-09-01&endDate=2015-10-01&prm1=3
I've been on it from 1.6 to 1.2, from looking at the video its around 1.2. The prime level for the Chilko is 1.5, big waves, Bidwell is pushy but manageable, there's a lateral wave on river right(entrance) that pushes you to river left where the holes are in the bottom left. Punch through the lateral with momentum and its easy to avoid the holes. Definitely scout it, it drops quickly and depending on the level there can be logs on the bottom left of Bidwell. I found at 1.6 some of the features got washed out, and 1.3 and lower is quite boring (whitewater wise) compared to 1.5.
Hope this helps.