[prae]

Thank you for your answer,

I read the migration guide, yes, and am aware of the automatic migration.
However, what I have to do is not that simple: not only we're migrating IFX version, but we are also merging different bases together.
I am looking for the best option, hence my question.

[Roelwe]

I think best you can do is migrate in diffent steps.
First migrate the instance and then merge yr databases.