I'm in the process of repairing my utility room floor prior to recarpeting
next week

I've laid a thin screed (10 - 25mm) in areas where the old damaged floor has
been brought up when I lifted the ceramic tiles & plan to finish off with
some floor leveling compound.

The screed was put down 2-3 days ago after sealing & priming the floor with
a solution of diluted PVA. The surface of the new screed seems to be
slightly powdery ~ is this normal or have I messed up the mix (I put a
dollop of FEB PVA into the screed also.

Should I use some concrete hardner/sealer before the leveling compound?

When do you think it will have dried sufficiently to put the leveling
compound down?

TIA
Mike