Whilst one can never be sure of what Schiit will do, I believe that this is highly unlikely.
They launched the previous models of Saga and Freya only 16 months ago, in May 2019, and have recently discontinued the solid state versions, Saga S and Freya S, as their sales were much lower than the tube versions, Saga + and Freya +.. Production of a new solid state Saga is therefore extremely unlikely and a balanced tube version would not fit in a Saga sized case; in addition, such a case size with only two balanced inputs and a single balanced output would not have enough space for even a single RCA input and an RCA output, thus would be balanced only. Moving up to the Freya size case, the savings from a reduced number of inputs would provide minimal cost savings and thus a product with little differentiation from the existing Freya +; it would also potentially make both the new preamp and the Freya + more expensive due to splitting sales across two models.
Whilst I would also like a solid state, Saga sized, balanced and single ended I/O preamp I just don't think it will happen anytime soon. I can't help thinking that any such rumour is simply wishful thinking.