How to change OLAP connection when going from dev to testing

Hi!

We created some BEX reports, a Dashboard and a some Webi reports using OLAP connections.

We created the OLAP connections with the IDT (Information Design Tool), and then publish them.

In the OLAP connections we used my user because we didn't have a specific user for connections.

Now they're going to create a user for the connections.

My questions is:

1. where do we change the OLAP connection? do we do it in the IDT and re-publish them or in the CMC --> OLAP Connections tab ??

2. are both ways correct?

Thanks in advance!

Florencia