Impact on Procurement and Financials when changing the Control Budget Setups

Content

We have implemented Financials and Procurement and using Budget Controlling/Encumbrance. Our Budget Segments are Entity and Natural Account.

We have 16 Business Units and as per the new requirement from business we need to perform below changes in Budget Setup:
1 - Remove budget controlling from few expense accounts
2 - Change Control Budget Name for all BU's
3 - Budget controlling segments should be Entity-Cost Center-Natural Account.

For this we are planning to perform new budget control setups for all BU's and permanently close the old budget controls.

Kindly let me know what things should we consider before closing the old budgets and defining new ones and will there be any impact on budget controlling or day to day activities.