There will now be no installation at the Royal Festival Hall in London in October 2013, but the machines will be at the Stafford Stamp Show Friday 8th November 2013 - Saturday 9th November 2013. There will be no overprints, but the machine(s) are expected to have Machins, Freshwater 3 Rivers, and Christmas Robins. The latter could be MA13-coded, see below.
UPDATE 25 September
Details have now emerged of the stamps available at Stafford:
Reel A = Robins (MA13)
Reel B = Machin (MA13)
Reel A = Rivers
Reel B = Robin (MA13)
Same configuration both days
Friday will have the ‘First Day of Show’ Receipt
Saturday will have the ‘Last Day of Show’ Receipt
The 'tour' for at least the early part of 2014 has been added in a separate post.