Data source rule are disabled

Hi nileshkemse ,
Thanks for the follow up and detailed explanation! Based on what you mentioned, your semantic model is using Direct Query mode and deployment rules have more limited support in Direct Query mode.
But not to worry, you can consider the following ways to move forward:
If acceptable in your scenario, switching the model from Direct Query to import mode will allow you to use the full power of deployment rules. This gives you more flexibility to handle switching data sources in different environments.

Fabric lifecycle management tools Frequently asked questions - Microsoft Fabric | Microsoft LearnIf switching modes is not quite feasible, you may consider manually adjusting the data source configuration in the target workspace. In Gateway Management in Power BI Services, you can manually set up and change data source connections for each workspace.
Even in Direct Query mode, although you cannot automatically change the data source by rule, you can still redeploy the model by manually reconfiguring the data source.
Solved: Re: Deployment rules in deployment pipeline - Microsoft Fabric Community

These are a few of the viable options available at this time, and I hope this helps with your question!