Update (1255ET): As Trump adviser Stephen Miller points out, the products are still "subject to the tariff under the original IEEPA on China of 20 percent."

The White House issued a further clarifying statement that the exemption (from the higher tariffs only) will be retroative to April 5th and all duties received since then will be refunded

Any duties that were collected at or after 12:01 a.m. eastern daylight time on April 5, 2025, pursuant to Executive Order 14257 and the Subsequent Orders, on imports that are excepted under Executive Order 14257 and the Subsequent Orders because they are "semiconductors," as explained in this memorandum, shall be refunded in accordance with U.S. Customs and Border Protection's standard procedures for such refunds.