A council has been sent to rework plans for its own development after councillors feared they would be “building a slum.” Maidstone Borough Council submitted plans in October for the redevelopment of the former Royal Mail sorting office on Sandling Road into three blocks of flats. Touting it as the “Maidstone East Regeneration”, the authority planned to turn the town centre site into blocks totalling 217 apartments. In the council’s previous Local Plan from 2017 the site was slated for “retail-led” redevelopment, but planning documents say that “has not come forward due to reduced investor app…