SPDY, Googlebot, Alternate-Protocol and SEO

We deployed SPDY on our production sites on Monday. It’s hard to tell precisely, but it looks like our pages are being removed from Google search results.

Some background. We used the Alternate-Protocol: 443:npn-spdy/2. Our http pages are INDEX,FOLLOW and our https / SPDY pages are NOINDEX,NOFOLLOW.

Could it be that Googlebot takes follows the Alternate-Protocol header, loads the https version of the page, and then doesn’t index it because of the noindex tags?

Can’t find anything in Google about this issue. Anyone else have experience? I’ll try to post back here if we find anything more definitive than pure speculation…