VodafoneThree: Finance Manager – Strategic Planning at Three UK

We’re creating something special. We are joining forces to create the biggest mobile network provider in the UK. Through our collective strengths and talents, we will transform customers’ experience and create a best-in-class network for coverage, connectivity, and reliability, delivering greater value and more choice for the nation than ever before. There are very few moments in our careers where we can feel the ground shifting beneath us, where we can sense that something bigger than we’ve known before is taking shape. We’re not just building a company. We’re going to build a culture, a legacy and a future to be proud of. This will require remarkable leadership and together we can set the standard in the industry and beyond for both customer and employee experience, in what it is a career-defining opportunity. Within this context, the CRO Developer plays a foundational role in supporting the organisation’s conversion rate optimisation agenda. Working alongside the CRO Manager, the Specialist helps design, deliver and analyse digital experiments across all brands, lines of business and customer journeys. This role contributes to the optimisation programme by helping shape hypotheses, build test variants, managing test setups and supporting with the QA and technical delivery of all testing. It offers a strong development path into a more senior CRO, UX or digital performance career. What you'll do  • Partner with CRO Managers to support technical feasibility assessments, sizing, prioritisation, and delivery across CRO, future capability, and personalisation roadmaps. • Collaborate closely with UX, Design, Product, and Engineering teams to create test‑ready assets and customer experiences. • Build and configure experiments across CRO platforms, ensuring high‑quality QA reviews and accurate implementation. • Use HTML, CSS, and JavaScript to deliver reliable CRO experiments with correct audiences, triggers, targeting, and measurement rules. • Monitor experiments in real time, ensuring sample balance, tracking accuracy, audience behaviour integrity, and overall experiment validity. • Maintain accurate documentation, including requirements, test logs, outcomes, and associated tickets. • Contribute to an open, learning‑focused experimentation culture, promoting continuous improvement and knowledge sharing across teams. • Provide guidance and training to Engineering colleagues on CRO best practices, supporting their ongoing development. •  Work effectively with technical and non‑technical stakeholders to deliver high‑quality tests, insights, and tracking implementations.