Hello Dhinesh,
You can use Shelf life day setup in Released Product > Manage Inventory Tab to auto calculate Expiry Dates
To reset the dates, you can open the Batches list page > Action Pane Menu >Reset , here you can reset all the dates including Manufacturing

Kindly let me know if this answers your query, kindly let me know if you have any further query
Regards,
Ashish
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