They treat sub levels as meaning only just, secure, and high. Apparently children should be expected to spend longer on secure or B than the other two, or so I was told at my training a couple of years ago.
I find this grid absolutely invaluable for identifying the next steps and setting expectations for outcomes in lessons. The document is called progress through the Sublevels in Mathematics and since it is based on the NC it is still relevalnt to the New Framework.
Much more accurate for sublevelling than APP IMHO :lol:
http://wsgfl.westsussex.gov.uk/ccm/cont ... ematics.en Hope it helps!