The zero rent shared ownership offer to resident homeowners is made to compensate you for the disturbance caused by having to move home to make way for regeneration of your estate. As a consequence, you would be able to live for the rest of your life in a home of considerably higher value without having to pay anything for this benefit. The council cannot justify offering to extend that benefit to people who have no prior connection to the location, nor have experienced any disturbance from relocation.
Does this answer your questions? If not get in touch