The situation
E.ON Next needed to move 2 million customers onto a new app and switch off the old one: two of the highest-risk programmes in the digital team, run together.
The problem
- Customers differ a lot (smart meters, complex tariffs, data quality), so moving everyone at once wasn't an option.
- The switch-off date was fixed, and a late surprise would have been costly and very public.
What I did
- Designed the rules for which customers moved when, based on data quality, meter type, tariff complexity and feature readiness, giving the business one clear view of who moves and why.
- Ran two testing approaches in parallel, one per customer group and one on an early production-like build, to bring the timeline forward by two to three weeks.
- Owned the final regression sign-off, and rolled out in stages while watching stability and customer sentiment before the hard cut-over.
- Stood up a launch task force when the date was at risk, and made scope calls on what to include and exclude.
A migration plan the business could see, explain and trust, and a launch that landed quietly.