“In the years of litigation over this issue, it has become irrefutably clear that the handwritten date serves no function in the administration of Pennsylvania’s election,” Matt Heckel, press secretary for the department, said. “As a result, the [PA State] Department has consistently argued in court that voters should not be disenfranchised for failing to write or incorrectly writing a date that serves no function.”
The ballots are all collected by the Sheriff's Office and delivered to the courthouse(?) daily or postmarked by USPS when received, no? Seems either way we know the vote was collected on time.