Hi Simon,
Quick question which I think I can guess the answer, does the current canonical page rank for anything at all?
Can't the developers make the canonical a static page (which currently redirects) default to the most popular and or a vanilla combination of product attributes?
That would of course be the best option, failing that you would have to just canonicalise to the most popular product variation and do so in a way that doesn't create a redirect chain.
I literally just referenced SiteBulb in another post, and I don't want to come across like a shill but there's a great explanation of it your issue here: https://sitebulb.com/hints/indexability/canonical-hints/canonical-points-to-a-redirecting-url/
Easier said than done for sure with some CMS and E-Commerce sites, but as the aforementioned link says...it's generally dealt with on a case by case basis.
Appreciate this is isn't a definitive answer but I hope it helps!
Nick


