Refresh it when the route, participants, official terms or professional scope changes, and before a material payment commitment.
Connect revisions to decisions
Keep versions so the household or sponsor can see why the total changed. Match each payment to the actual stage and verified instruction. A fully funded budget may improve readiness, but it does not settle the time needed for review, availability, an interview or the intended move.
Refresh the budget on defined triggers rather than on a schedule, and keep the earlier versions so the household or sponsor can see what changed and why. The triggers are a change in the route, in the participants, in the official terms or in a professional scope, together with any material payment commitment, since that is the moment an unverified figure becomes expensive. Match each payment to the actual stage it belongs to and to a verified written instruction rather than to a summary.
A fully funded budget improves readiness and settles nothing about the time required for review, availability, any interview or the intended move. Note who is responsible for noticing when a trigger occurs. Agree in advance who reviews the budget and how often.
Where a trigger passes unnoticed, treat the budget as out of date until it has been rebuilt.