As Cartman said above.
However it is not an automated level bust detection - it still requires the ATCO to check the SFL on radar. Most times they will, sometimes it is just too busy, or like anything, mistakes will be made and we may rwad what we want to read and not what is actually on the screen (false positive).
Automated checking is one of the benefits that will happen with the introduction of electronic flight progress strips - one of the main reasons that management are pushing the introduction.
Unfortunately management don't seem to realise that the benefits might be outweighed by the detrimental aspects of EFPS versus paper strips - but that is another argument.
As Cartman says, you could have the correct level selected, but the wrong QNH - there is no facility for detection of this.
I e-mailed an engineer a while ago with what I thought was a fairly simple solution for having the wrong pressure selected (considering NATS has some very clever engineers who did wonders with Mode S and Vertical Stack Lists).
Unfortunately he didn't even respond to th ee-mail, never mind actually saying wheteher it would work or not
