In Victoria your property’s overlay provides an indication of the level of bushfire risk, the building and planning controls plus how much vegetation you can clear without a permit.
What property overlay are you in?
In Victoria a Bushfire Prone Area planning overlay (BPA) forms a trigger for you requiring to build in a particular way. So, it's a building control. This is where you might be required or asked to build a specific way to a certain BAL level using a standard such as AS 3959 or the NASH building code.
It's an area where it's considered that fires are frequent and severe enough that it warrants a specific approach to build in response to that risk of fire arrival.
Within a BPA area you get the opportunity to consider certain types of vegetation management - called a 10/30 rule.
Bushfire Management Overlay (BMO) is an area within the BPA, a sub-area of a BPA thats of particularly high risk. So, the fires within a BMO are particularly severe and therefore warrant additional requirements which are called Planning Controls where specific setbacks and extra measures are required if you plan to build and therefore need a Planning Permit.
The Vegetation Management options you have within this BMO area is called a 10/50 rule, which is quite similar to the 10/30 rule, you can just do a little bit more.