Richmond firefighters and police officers anticipating that long-promised raises would appear in their paychecks this week were told Tuesday that they may have to wait until September. They will still receive the additional money as back pay, but union officials say they’re worried that some employees may have been counting on receiving the raises as planned. Mayor Levar Stoney’s office blamed the delay on new oversight rules passed by the City Council, which require his administration to seek approval for some budget transfers within city departments.