Time Frame for Upgrading the Front-End Software
Use
The new SAP system release cannot run until a compatible version of the front-end software (SAP GUI) has been installed. However, as the front-end software is compatible with several SAP system releases, you may not have to upgrade to a new front-end software release.
If you need or want to use a different front-end software, you can import it as soon as you receive the software package. If the front-end software you are using on the source release is not compatible with the target release, the latest possible time for upgrading the front-end software is before you start the shadow system for the first time in the START_SHDI_FIRST phase during roadmap step Preprocessing.
If you choose scenario strategy Standard or Downtime-optimized, this phase is part of roadmap step Preprocessing.
This graphic shows the time period during which you can upgrade the front-end software:


