Currently working on a complete front-end and back-end overhaul of our webapp. We did this because a lot of changes needed to be made to the database schema as well as the user experience.
Now we are almost done with the overhaul and I'm thinking if we could have taken a more incremental approach? We started a new codeline for this overhaul and now we have to figure out a good data migration plan to make sure the old data is transferred over to the new schema properly.
We made the decision to do a separate codeline because we thought that if we did incremental changes to the schema, there would be more downtime to the site. A separate development cycle for it would reduce that downtime to the final day when we do the data migration. And of course that carries more risk.
What are some good approaches to this problem for the future if we ever need to do another major overhaul? Incremental approach would be desirable.