Acess serial data via GATT service

Hello,

I am trying to access the serially transmitted data from a simpleRTK2B GNSS module via GATT.
I don't understand what baudrate I must set and what else needs to be done to correctly receive the needed data. Read this forum post for more context: https://www.ardusimple.com/question/con ... ment-28200

Can anyone give me some hints? Is this even possible?

Thanks in advance!