In that instance I would do BT around 12hrs after wu. It's a really difficult one to call as it really does depend on your lO's temperament. Mine didn't like a long A to BT I discovered as it caused early NW's that we're easy to resettle. If I put her to bed too early she'd naturally wake after 11hrs anyway so I was hesitant to do too early a BT. Think I did 6 as our earliest when she only did an hour nap.
I would usually work out how much sleep they need overall. So if she usually has 2hrs DT sleep and 11hrs ONS sleep, for your routine today I would only do BT 30mins earlier. Do you see what I mean? Xx