The promotion possibilities are relatively set within the business and could be less restrictive. The general idea is that there are not as set positions and roles and the structure is relatively vertical, however, early on it is clear that you have to wait the required time before moving up in the ranks. This helps create a sense of education, responsibility and balance, but as always I do believe there is some discrepancy between the roles. An example of this is someone might come in with a lot more experience than someone else but not necessarily get the role.
Promotion possibilities are rarer than they should be for the company, however, exit opportunities are vast.