Answer:
Yes, additional pressure and heat will lead to further metamorphism. The reference used to describe this is called the 'degree of metamorphism'. For instance, the sedimentary rock shale can become the low grade metamorphic rock slate. In the next degree of metamorphism, slate can become phyllite. Phyllite can then become schist, and finally gneiss. Migmatite is the highest grade metamorphic rock, but has been partially melted.