State tax filing

Also if it was required, why did that not show as an option when I file for an extension using 4868 using TurboTax. 

note : my file by mail instructions for both state and  federal have independent mailing addresses for both types of returns and both say deadline : Oct 16, 2017 ..,.. Meaning my 3 year statute should be until 10/16/20 for both state and federal.  

If form 4868 did not apply to both federal and state extensions in 2016, why does my mailing instruction note the deadline as being in October ? And again why didn’t TurboTax offer a state extension link ?