Interesting question but it is difficult to answer without knowing more about what sort of academy it is and what is in the academy’s funding agreement. As a matter of principle academies are supoposed to follow the Code of Practice on Admissions but some academies have arrangements as part of their funding agreement that allow variations in catchment area and over subscription rules.
YOU can apply for the funding agreement via a freedom of information request to the school or the Dept of Educ ( via the theyworkforyou website .
*******BUT you must specify you want all further correspondance covering amendments to the funding agreement as they don’t issue a new agreement everytime a variation is made. This is how under-counter changes get hidden.YOU have to be very very specific otherwise they just send the superseded funding agreement without details of variations******
YOu can also apply to the Local Authority for info regarding the notification the school should have given them regarding any changes and the rationale behind them. You will have to compare the previous LEA admissions policy with their new one.
Do you know why they’ve done it. HARROGATE gRAMMAR, A VERY POSH COMP have always allocated 79% of places to the urban catchment and 21% to the rural area around Harrogate.These splits are then allocated by closest distance to school ( which neatly puts the council estate kids in the north-east in the struggling Harrogate High. But this was under the right wing NOrth Yorkshire LA before as well.