OK, difficult to know what your employer may see as your role, but brush up on basic mathematics (useful for any load planning or loadsheet/mass and balance work) and familiarise yourself with IFR flight plans and basic aviation meteorology (how to decode TAFs and METARS). If you have an aviation background already then this will be familiar territory.
Other than that, not much else I can think of that you might be able to do. The greatest challenges you are likely to face are things you cannot really study for - people skills, time management, organising and prioritising your work, and troubleshooting through problems.
It's a fun job and I'm sure you'll enjoy it.