Interim Senior HR Business Partner – Transformation

Company: Middlemore
Apply for the Interim Senior HR Business Partner – Transformation
Location: West Sussex
Job Description:

Interim Senior HR Business Partner – Transformation

Location: Sussex (preferred) | Birmingham / Manchester considered | Hybrid (c.1 day/week)

PE-backed, high-growth organisation

£600–£700 per day (outside IR35) | Immediate Start | Until End of Year

Middlemore are partnering with an entrepreneurial, private equity-backed organisation to appoint an Interim Senior HR Business Partner to lead a sizeable transformation programme.

This is a high-impact role embedded within a business undergoing rapid growth and significant change, driven by investment and a focus on automation, AI-led service delivery and achieving operational efficiency.

The opportunity…

You will act as a senior, hands-on HRBP aligned to a 600-FTE client group (mid/back office) and lead the people agenda for a large-scale transformation programme which will see a streamlining of the function as efficiencies are made through Ai/Tech .

This is not a traditional advisory role, you will be responsible for owning and delivering change end-to-end, working closely with senior operational and transformation leaders.

Key responsibilities…

  • Lead organisation design and workforce planning, defining the future-state operating model
  • Translate strategic transformation goals into practical, deliverable people plans
  • Deliver restructuring programmes, including consultation and redundancy processes
  • Partner closely with Operations leadership to drive efficiency and cost transformation
  • Own the people communication strategy, maintaining engagement through change
  • Provide credible challenge and insight to senior stakeholders
  • Ensure alignment between HR, Operations and Transformation teams

The Context…

  • High-growth, PE-backed environment
  • Significant transformation agenda including automation and new-systems implementation
  • 600-person client group, UK based.
  • Likely workforce evolution including role redesign and reduction by 20-30%
  • This role will own and deliver the people side of the transformation end-to-end, with support from a HR Advisory team.
  • Fast-paced, evolving environment with strong leadership visibility

What we’re looking for…

  • Experienced Senior HRBP / Transformation HR Lead
  • Proven track record delivering organisation design, workforce planning and restructuring
  • Experience in PE-backed, high-growth or complex transformation environments
  • Strong employee relations expertise, including consultation processes
  • Highly commercial, pragmatic and delivery-focused
  • Comfortable operating hands-on at pace in ambiguous environments
  • Confident influencing and challenging senior stakeholders

Why apply…

  • Opportunity to lead a business-critical transformation programme
  • High visibility with senior leadership and transformation teams
  • Work within a fast-growing, PE-backed business
  • Immediate start with strong day rate

If you’re an experienced HR transformation specialist who thrives in fast-paced, delivery-focused environments, we’d love to hear from you.

Posted: April 1st, 2026