create a project start date change using fusion from scratch.

@himabi Just checking in. Were you able to resolve your issue? We’d love to hear how things worked out. If the suggestions above helped, marking a response as correct can guide others with similar questions. And if you found another solution, feel free to share it — your insights could benefit the community. Thanks again for being part of the conversation!

Hi @himabi,

Please take note that there are three start and three end dates that you have in Workfront (Planned, Projected and Actual), please check the following documentation on how certain fields are calculated/set. 
https://experienceleague.adobe.com/en/docs/workfront/using/manage-work/projects/plan-a-project/proje...
https://experienceleague.adobe.com/en/docs/workfront/using/manage-work/projects/plan-a-project/proje...
https://experienceleague.adobe.com/en/docs/workfront/using/manage-work/projects/plan-a-project/proje...

If you want to set the date which you see in the list overview that would be the Planned Start Date and/or Planned End(Completion) Date per documentation those fields would be plannedCompletionDate (calculated by system per project duration based on Planned start date) and the start which you can set is plannedStartDate.

Also please refer to the/workfront/setup/projects endpoint in workfront where you can configure Project time calculations.

Hopefully this helps.

Best regards,
Ivan Bebek