IIRC, and frankly I don't trust my memory any better than, um, I forget. What was the question?
Oh, yeah, IIRC, the "center block" was just a slight beefing up of the central area of the bridge/pickup area to reduce feedback, not a complete center block like on a Gibson 335 or other true semi-hollow. And the design hasn't changed since that mod was introduced with the 25th Anniversary HB II back in 2010?
And I think it got introduced at the same time as the SC Hollowbody II. The SC HB I was pre-2008 based on my brief internet searches, and the SC HB Standard was a 2008 offering. The earliest reference to a SC HB II I can find is from the 25th Anniv models in 2010 (or late 2009, perhaps). All results for "2009 singlecut hollowbody II" are really SC HB I models, AFAICT.
Now, that being said, it wouldn't surprise me at all if PRS did minor un-advertised tweaks to their design and that if you x-rayed or deconstructed various SC HB IIs from over the years they might look different in subtle but important ways.
