On WSO, we get a lot of questions from professionals in the middle orpositions of a financial services group that are trying to get to the client facing / positions at that firm (like M&A in IB). While this transition is possible, it is exceedingly rare and usually takes several years of networking and persistence.
The reason is that thepositions have an extremely structured recruiting process (OCR) and there is usually no reason to promote a non-traditional candidate internally unless they come highly recommended. It is also difficult for your boss to recommend you for positions when they want to keep you.
Again, this is where networking across divisions within your firm early and often can pay off. If you want to be the exception, you will have to be an extrovert and demonstrate not only the technical capability, but also the soft skills to navigate this rare transition.