If you have applied for entry in 2015 this change will make no difference at all. They have to stick to their published admission criteria for this year. The cannot prioritise people in the catchment area until next year.
I guess you could appeal as I suspect that the admission policy is currently out for consultation? What does the policy say? Are there any places for out of catchment? Some grammars allow a certain number of open places, but otherwise if you are out of catchment, then you would only get a place if there weren't enough people living in catchment who passed the test and wanted a place.