In an ideal world, it would be nice to work as follows.
Current site for example is 4.2.4
Upgrade to 4.3.1, 4.3.2, 4.3.3 and 4.3.4 on a development site
Be nice to diff between 4.2.4 and 4.3.4 so changes can be reviewed and updated. in client source base (without having to do this for each incremental upgrade since I don't have confidence that upgrades report proper conflicts).
I should then have a development 4.3.4 site that has all current files and all local customizations that are required applied. I can then thoroughly test this development site.
My process would then be to:
- close the production store
- Upgrade production from 4.2.4 -> 4.3.1 -> 4.3.2 -> 4.3.3 ->4.3.4 (this will ensure the DB is correct)
- Copy the development site files to the production site (should have local changes applied)
- Open the store
- This production upgrade should take less than an hour and have complete confidence in the results.