There is no option to extend the timeline. But we have an Customer influence to extend this from 2 months to 4 months which is planned in our roadmap for the end of this year release. https://influence.sap.com/sap/ino/#/idea/242531/?section=sectionDetails
Thanks & Regards,
would you mind to elaborate on your question a bit more? I would like to understand your use case(s).
What are you trying to achieve in general? What is the typical workflow (user story) of your users? What exactly are they struggling with at the moment?
Why is it important that your users can select such a long timeframe?
What do you expect to see on the planning board when you select e.g. 1 Year?
How long do activities you assign to resources last on average?
Many thanks and kind regards,