It has been awhile since I completed my BA degree. Would it be sufficient to get recommendations from my supervisor or a colleague at work for the application?

The purpose of the recommendation letters is to provide the committee with evidence that you can be successful in an academic setting. Our experience is that letters from at least one college instructor provide a more complete picture of an applicant's potential for scholarly work. It's usually worthwhile to ask a prior college instructor if they will write a letter - they often remember students longer than you might think. If you cannot obtain a letter from a college instructor, we recommend that you carefully consider how to provide evidence for your ability to be successful in a graduate program in your personal statement or with alternative documentation.