An addendum can replace a whole schedule, selected pages or only a line description. Treating every amendment as a complete replacement is as risky as ignoring it.
Build an impact note
For each addendum, record the issued date, acknowledgement requirement, affected document, replaced page and budget consequence. Keep the note beside the controlled document index.
Lock superseded pages
Move old working pages out of the active pricing set while preserving them for the audit trail. Use filenames that state both version and status; “final latest” is not sufficient when several people are editing.
Reperform affected calculations
Changed quantities can alter section totals, preliminaries, fee percentages and VAT. Recalculate downstream values rather than pasting the new line into an old summary.
Confirm acknowledgement
Check where the addendum must be listed or signed. This administrative act is separate from updating the budget, and both need completion before the submission is sealed or uploaded.