Question on the mobile version of PSD templates

Hi.
I have a question with regards to the mobile version of the basic PSD template.
Is this requirement mandatory for PSD category on the TF?

Let’s say I’ve got a PSD template which is based on bootstrap 3 grid (1170px), whether to do under: 970px, 480px, 320px?

I understand that it is desirable to do so, but is it a requirement?

Thanks for the answer.

No is not.