By MARG JACKSON mjackson@oakdaleleader.com Describing it as a ‘legal matter,’ a U.S Postal Service employee in Oakdale said no one in that office could comment on the ongoing closure of the Community Post Office, CPO, in Knights Ferry. The office in the historic hamlet had been operating for more than 150 years, open in recent years for a few hours daily during the week, but abruptly closed with the unexpected passing of longtime postal contractor Sherron McCarthy. She passed away in late March.