Forecast Planning x Budgeting

Hi All

I'm a financial consultant but not expert in the Budget x Forecast module.

One of my customer does the annual Plan budget and the monthly forecasts are loaded into JDE at the beginning of the financial year.

The budget revisions (twice yearly) are also loaded in but they.

I need to know if is possivle to load re-forecast monthly budget spreads into JDE when they revise the budgets?

I'm a little bit confuse about the difference between Forecast Planning x Budgeting ?

Many thanks in advance.