People who missed the income tax filing deadline last week might not be contacted by the Internal Revenue Service immediately. But make no mistake: Those who are supposed to file will hear something eventually. “They’re not going to hear from the I.R.S. right away,” said Cari Weston, director of taxation at the American Institute of Certified Public Accountants. It takes time, she said, for the agency to receive all the forms necessary to reconcile returns, so non filers may