People on the other forum are speculating bonus stuff for each individual era...seems to me they didn't pull the OBC and Meddle 5.1 completely out of thin air, it had to come from something.
Of course we are just speculating, but I would be one very mad fan if I purchased this very expensive set and six months later they released the contents individually with "new" bonus material added on. I would be drafting hate mail immediately....so, no I wouldn't expect those with a newly remixed surround version. I truly can't wait for the next set though 1973-80's......there is a big prize lurking in there I hope.