You can apply both BP and Moisturizer at both night and before you go to bed.
For a bit of guidance here is my personal regimen as a guideline___________
Morning
-Cleanse face lightly with 'Simple' gel wash whilst i'm in the shower
-Lightly pat face dry, then once my face is completely dry ... I then apply the BP [Full index fingers length]. Apply this evenly and gently, it's all about being as gentle as possible [Less irritation means less acne =) ]
-Once your BP has now completely dried [i like to go off and do others things round the house to occupy me whilst this drying process happens] you can now apply your moisturizer [i recently started using 'Garnier' aloe vera 24hr body lotion] it works fantastic at hydrating and soothes redness that you'll get from the BP.
Bedtime
EXACTLY THE SAME AS MORNING
Any other questions just =)