Final answer:
The statement is false; married taxpayers who file separately can typically file an amended return to change to a joint filing status within three years from the due date of the original return.
Step-by-step explanation:
The statement 'Married taxpayers who file separately cannot later (i.e., after the due date for filing) change to a joint return' is false. Generally, married couples who originally choose to file separately have the option to amend their returns and file jointly within three years from the due date of the separate returns. This does involve submitting an amended tax return using Form 1040X for the relevant tax year. However, there are specific conditions and certain types of income, such as unemployment compensation, which might affect eligibility for different filing statuses, as indicated by the requirement around the total being over a certain threshold as indicated for Form 1040EZ referenced in the question.