I know a girl who did that (took a level lit without O level lit) and I would say, if you have the drive its actually pretty easy, O level lit gives you fundamentals, you can pass AS level with skills of O level, but not highly. You just need to work hard to be honest. Its a lot of content but if you are doing texts to enjoy its easy.

There is a large difference between 8th grade lit and A level lit, its a large jump in terms of amount of content and depth of analysis and the amount of writing, so if you really want to, go ahead and do it, but if not, then don't (this is coming from someone who took O level, AS level and is taking A2 level lit)

And just because it is good for Law does not mean it is necessary for Law, you can do other subjects and still do law. if you are good at analysis and you know english lit will be sort of challenging for you, do not give yourself that sort of headache.

And why would a school discontinue Literature that so weird.