Florida Landlord Law has a State required 'NOTICE' form that must be filled out correctly. If this form is not filled out and served correctly, then the 3 DAY NOTICE is defective and subject to dismissal by the Judge. The addition of '6pm deadline' would make the notice defective as State law does not allow such requirement. You should reissue a 'proper' 3 Day Notice' as required by State law and correctly fill it out and properly served it. I will gladly post the form and instructions if you need them.