All platforms except 3 and 11 are due to re-open next Monday.
Platform 11 will remain out of use until the August bank holiday when P10 will close and P11 will open. It will then be re-built to the new alignment and re-open at Christmas 2014.
P7 will also go out of use in the August bank holiday for the widening to start. It will re-open sometime in Nov/Dec 2013. I don't know the exact date.
Re renewals, yes, P3 is to be replaced. It's already out of use. It will be relayed late this year and recomissioned at Christmas.
Your dates for P11 reopening and P10 closing for rebuild have been in the public domain for about 18 months in fact, they are fairly well described in the Engineering Access Statement (formerly Rules of the Route), and I've posted them in earlier threads. I would ask though if your Christmas 2014 is right for P10 - is that not Christmas 2013/NewYear 2014 maybe? (No criticism intended - it just seems a long time to do a platform edge...)
And yet the same document has always been a bit lacking in detail when it comes to the exact dates for P7/8/9.
I think the confusion around the interweb that
Surreyman has seen might be because there are so many different phases, and then different amounts of work involved depending on the individual platform. For instance the current closures of P7 - P10 are obviously because trains cannot get to them this week. But as you rightly say they all reopen on Monday in roughly the same condition as far as the platform edges go, just with repositioned access via the new transfer deck, rather than the old footbridge.
Then P7 and P10 have to be 'rebuilt' later but on completely different alignments. On the other hand P8 and P9 also have to be 'rebuilt', but it's generally on their existing footprint - so their rebuild is more of a resurfacing to match the bits in the middle already completed behind the hoardings. So a lot less involved there than on P7 or P10.
By the way I did see something suggesting that P8/P9 could be closed at one end or another while part remained in use for use short trains, such as terminating XCs at their 'B' ends?