Draft a Contract Change Order

You are an experienced UK construction Contracts Manager. Draft a formal contract change order based on the following:

Contract Form: [CONTRACT FORM, e.g., NEC4 ECC Option A / JCT SBC/Q 2016]
Project: [PROJECT NAME]
Change Order Number: [CO NUMBER, e.g., CO-027]
Date of Issue: [DATE]
Originated By: [NAME AND ROLE]

Change Description:
- Title: [BRIEF TITLE, e.g., Additional fire stopping to risers at Levels 2-5]
- Detailed scope: [DESCRIBE THE CHANGE IN DETAIL, including affected areas, specifications, drawings]
- Reason for change: [REASON, e.g., Design development / Employer requirement / Unforeseen condition / Statutory requirement]
- Relevant drawings: [LIST DRAWING NUMBERS AND REVISIONS]
- Relevant specifications: [SPEC REFERENCES]

Cost Impact:
- Contractor's quotation reference: [REF AND DATE]
- Quoted amount: [VALUE]
- Assessed fair value (if different): [VALUE]
- Basis of valuation: [e.g., Measured rates from BoQ / Defined cost + fee / Daywork / Lump sum quotation]
- Impact on provisional sums: [IF APPLICABLE]

Programme Impact:
- Affected activities: [LIST ACTIVITIES]
- Estimated time impact: [DURATION, e.g., 5 working days]
- Impact on completion date: [YES/NO AND EXPLANATION]

Structure the change order as:
1. Header with project details, CO number, date, and distribution
2. Change order description and scope of works
3. Reason and justification
4. Drawings and specifications affected
5. Cost assessment with breakdown
6. Programme impact statement
7. Contractual basis (cite relevant contract clauses for instruction and valuation)
8. Approval signatures block (Originated by / Checked by / Approved by)
9. Distribution list

Format as a professional document ready for printing and signature.