I don't think BTFP is a form of QE. I think is a form of Yield Curve Control. Debt instruments are not being sold to the market by banks because they can use them as collateral at face value to get loans to solve their liquidity problems. This can help putting downwards pressure on the yields (or at least as a relief of upwards pressure). In terms of domestic US liquidity, this is possibly offsetting upwards the contraction of liquidity by the other programs (reducing Fed's balance sheet; re-filling treasury general account). Decreasing reverse repo done by the Fed is also offsetting the liquidity upwards as it leaves more cash in the commercial banks.