My first ever post on BW was about doing a SEBT for DD1 on the first day that she went without a nap, and that I only had the guts to try it because of other people's experiences that I'd read on here. I went as early as 5pm with her and, like aishi, we got some 14 even 15hr nights. She has also been a good sleeper in general, so maybe not as scary as trying it for B! It never backfired though. Couldn't hurt to see what happens?