Some of the optional modules incorporate PBL - it depends on which you decide to take.
For example, if you choose a module which is taught jointly with another department (such as philosophy or politics) they tend to use more traditional lecture/seminar structure. Though modules taught entirely within the law school (for example, Company Law, or Competition Law etc) tend to incorporate PBL in some form.
I'm still around at YLS next year, so will see you in the PBL area come October then!