During migration, you are running two worlds. If you do not explicitly design the operating model, teams burn out, delivery slows to a crawl, and the migration becomes the only thing anyone can work on.
The operating model is what keeps the program boring: who owns what, how work gets prioritized, and how incidents and cutovers get handled without drama.
You are trying to do three things at the same time: keep the legacy platform stable, build and prove the new platform, and move consumers while shutting legacy down. If the operating model does not make this tradeoff explicit, it turns into chaos.
Start with roles. You do not need a complex org chart, but you do need clarity.
For each wave, name a legacy owner who keeps the current world stable, a new-world owner who builds and runs the new capabilities, and a consumer owner who is accountable for dashboards, apps, and models. You also need a migration lead who can make sequencing decisions, resolve tradeoffs, and manage risk.
Make support predictable before you add load.
Decide support hours and escalation paths. Define how incidents get triaged across legacy, new, and the bridge. Decide how you communicate changes and cutovers so consumers are not surprised.
Routines are what keep progress steady.
Run a weekly migration sync that is focused on decisions and blockers, not status theater. Do a wave kick-off and a wave close, and use the close to confirm cutover stability and decommissioning actions. Keep stakeholder updates framed around outcomes such as continuity, improved UX, and reduced cost.
Most teams fail here by trying to do migration “on top of everything.”
A practical default is to reserve a fixed slice of team capacity for migration (often 20–40%), keep a protected slice for business delivery, and only increase migration capacity when the organization is seeing tangible wins.
You will know the model is working when incidents get handled quickly because ownership is clear, teams can explain what is true because the source of truth is explicit per wave, and parallel runs are time-boxed instead of drifting forever. Progress should also be visible in simple terms: waves completed and legacy surface area reduced.