Once you have evaluated the need for budget re-allocations, you should assess the scope of changes the budget needs to go through
You should understand the rationale of your changes to be able to communicate them to the funder
You should understand what is possible under the grant agreement before incurring unplanned expenditures
A mistake that will easily make your costs ineligible is spending savings made in one budget line on increased expenses in another
Your donor can be more flexible than you may think. Don’t hesitate to reach out to them.