You have to complete a year of postgraduate training before you can apply for the LMCC designation.
It used to be that you needed that MCCQE part 1 and 2, but they got rid of part 2 recently. It was quite a lot of money, and just knowing human greed... many people have thought there's likely going to be some sort of replacement test coming in the future. [It is a lot of money on the table...] It still costs a a couple hundred dollars for some reason.
Though once you have the designation, you're good. You also need to do it for registering for licensing exams (CFPC or Royal College)
All in all, July of your PGY2 year, apply for it.