Budget programme structure is the relationship between plans and budget so it provides in important link between the objectives of the business and the details of a budget.To be able to link the budget programme structures you should put the main areas of responsibility.
So for the budget programme structure, you should provide a stable framework to get a successive plans and strategic so the importance is the budget allocation and performance indicators.
So when a budget programme structure is determined it shouldn't be change and should be noted and stay focus and using it for a year or even a cycle of 5 years.
However if in a business they change their policy, the programme structure may have to be changed but in many cases the new policy is related with the activities of the business.