Using existing domain

[WMESN]

Hello GA app Team,

Firstly, thanks for creating such a user friendly app. I want to deploy this application for ESN Germany, so I had small question is it possible to use it with existing domain by creating sub-domain (eg: ga.esn-germany.de) as we already own it rather than creating a whole new domain in the aws as per the instructions(eg: ga-assembly.link).

Thanks.