Only on the STO forums can you ask a question and ppl answer with anything but a answer. I see by the answers gather as a "no" since everyone is still guessing
Your question has two meanings. Yes, we have heard word of a new Defiant Variant - all the T2-4 ships are getting Variants. No, we do not know when it will be released. We did not know when the new Galaxy and Vor'cha ships coming until they went to Tribble last week.