Hi Prabhjot,
We need a bit more detail to understand this issue. Was the screenshot taken from the PAW cube viewer? Or is this a Websheet that has been embedded into a Workspace book? Is this a picklist cell from TM1?
I did quickly take a look at our calendar user interface in the Workspace cube viewer (which looks very different than your screenshot) and there doesn't appear to be a way to limit the date range. You may want to open an enhancement request around input validation. I also think you may be able to use a picklist cell in TM1 to limit the dates the user can select. Picklist can be dynamic (based on rules or dynamic subsets) if you need to allow for the selection of a changing range of dates.
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Stuart King
IBM Planning Analytics Offering Manager
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