Leaseholders who are not resident on the estate are not entitled to a new property. This is because they do not have a housing need as they are living elsewhere already. They will be receiving the full value of their property as well as receiving 7.5% of the value in additional compensation. If part of the redevelopment were to include additional sale properties, then they would clearly be able to purchase one of those new properties.
Does this answer your questions? If not get in touch