^ What Amy said.
The cast normally goes back to filming around October. As far as airing, it depends on the lineup they have. Switched at Birth being an older show, currently the second oldest behind PLL, could be pushed back if they want to introduce a newer show in January; however, I think the network has been satisfied with the combination of SAB and The Fosters in the 8 and 9 o'clock slots.
As long as it's been on though it has been given a January premiere. That's not to say it couldn't change or even that it will change, but there's always a possibility.
*fingers crossed that we get a fourth season and it gets a January premiere because waiting until March would suck
*