In an effort to cushion full-time residents from increasing costs, Tybee Island officials on Wednesday signed off on rebates to weekly garbage pickup services for those who currently receive homestead or senior exemptions on their property taxes. The decision comes just two weeks before a contract with a new solid waste collection provider, Pooler-based Atlantic Waste, takes effect. The Tybee City Council last month approved a six-month trial with Atlantic that provides residents and businesses with side-door trash and recycling pickup and residential yard-waste pickup.