Something important to remember is that as a lawyer, your reputation is everything. You start building this reputation as soon as you enter law school, and you should get used to considering how your actions, words, and commitments during law school may reflect on your eventual reputation as an lawyer.
How the above relates to working during law school, is that if you choose to do so, you should be prepared to be open and ready to explain how your work commitment affects you, and why it may limit your ability to participate fulsomely in law school life at times. For example, you can expect to do a non-insignificant amount of group work- both in classes, and outside. You will need to be prepared to explain clearly what your work commitment entails, and should do so at the earliest opportunity, so as to ensure your colleagues can plan appropriately. You do not want to be the flakey student, who can never meet at times that work for the rest of your team, though has not communicated why, or attempted to compromise their schedule for the benefit of the team as a whole.
UBC has no problem accepting 3rd year candidates provided you have the requisite credits. Are you sure you don’t want to finish your degree? I know some people who’ve expressed regrets about not finishing their degree but it’s not otherwise a hindrance in getting a job, all things being equal.