They issued the Dunmore proclamation at the start of this episode. Notice the British freed only the slaves on the patriot side and allowed loyalists to keep theirs.
http://www.upa.pdx.edu/IMS/currentprojects/TAHv3/Content/PDFs/Dunmore_Proclamation_1775.pdf
Well, well. Dunmore was genuinely concerned about the situation of the slaves. /S
I’ll watch for that when I see tonight’s episode. I’m hoping “TURN” does well enough in the ratings to get renewed for next season.