When is open access not open access? When you can't access the supplementary material

Important update 2014-11-12:

I was contacted by Genome Research again and the Supplementary material is now available. Seems like the earlier email saying that it would take months was in error. 

There is a new paper that has recently been published by Genome Research as an 'Advance Online Article':

This paper, by Detlef Wiegel's group, looks like it will be extremely relevant to a project that I have been involved with. The paper describes a 'detailed Hi-C map of the three-dimensional genome organization of the plant Arabidopsis thaliana' and I would love to see full details of this map.

As I read the paper, I quickly realized that they describe a lot of results. The main paper itself is relatively lean with just six figures, but these are accompanied by thirty-one figures and ten tables in the supplementary material. However, as this is an Advance Online Article, the supplementary material has not been made accessible. I contacted Genome Research about this and they told me:

You won't see any Supp Material for the article on Genome Research until the full article publishes which should be sometime early next year.

This is somewhat frustrating. The paper is open access which is great, but if so much of the data behind the paper remains inaccessible for maybe another 2 months, then it places limits on the current usefulness of the paper. Assuming that the supplementary material exists as one or more documents, I really can't understand why a journal can't just make a provisional PDF file of the material, just as they do for the main paper.