I noticed that on the LBS web site they say that although the applications for the MBA starting in August have closed, they are still considering late applications.

Is it worth even trying though? How likely are they to accept an app at this point?

They always leave a few seats empty for high quality candidates whose plans change. You'd have to be not only be more able than the people on the waitlist to bring something unique. You'd have to be better than most of the people in the admitted class. So if you are not mearly a strong candidate, but also one that most top schools would consider for scholarship, then give it a go.

[Edited by Duncan on Apr 18, 2019]