Need to upload revised App Store binary - how?

I submitted an app to the App Store and they asked me to make some changes (it was a "demo" version which apparently is not allowed) and upload a new binary using iTunes Connect. However on iTunes Connect you can only change the metadata, large icon and screenshots, but there is no way to upload a revised binary. I suppose I could resubmit as a new application, but then I will need to rebuild my code with a new bundle identifier which is kind of stupid, though possible, and also the new submission would probably come in at the end of the App Store review queue instead of being associated with my old submission. Anyone had a similar problem and can suggest anything? I think in the meantime I will put the new binary on my website and mail devprograms the link, will update later if it worked.