The problem is that for years there have not been enough secondary places in Reading, so Reading children have been going to Maiden Erlegh, Bulmershe and Ryeish Green - far more than Wokingham children going to Reading/Kendrick.
Of course, of the three, it was Maiden Earlegh that the parents wanted to get their children into, as it had the best results, so lots of people bought houses close to the school, but actually in Reading Borough, not Wokingham - areas where children traditionally got into ME. Meanwhile, children living in Earley were unable to get in to what was actually their closest school, and the perception of their parents was that they were being pushed out of a school that their council tax paid for, by children whose parents paid tax to another borough that wasn't making adequate provision for their secondary pupils.
However, now that Ryeish Green is closed, it's Wokingham that is also in danger of not having enough secondary places, or at least not in the right place, with St Crispins, the Emmbrook and the Holt all being so close together and, unless and until they move the Emmbrook, no secondary at all in the south/east area.
So now Wokingham BC have reorganised the catchment areas and introduced a system which is too complex to explain here, but which effectively means that most of the people who bought expensive houses hoping to get their children into Maiden Erlegh will now find they can't get in. Wokingham BC have said that their intention is not to exclude children from Reading, but that statement is generally taken with a whole bushel of salt...
It seems as if the campaign to change the Reading School/Kendrick School admissions criteria is an attempt to make these two schools into a Maiden Erlegh substitute.
A further twist is that Maiden Erlegh is now an academy and so could presumably set its own admissions criteria, though so far all they have said is that there will be 'continuity of approach' and they will 'continue to work closely' with other schools in the area and with Wokingham BC.
Watch this space.
(Incidentally, I agree with those who say that Reading School is not full of children from private primaries, at least not when DS was there - the majority of his year were certainly from state schools. But he left in 2006, so things might have changed since then)