There are two types of date picker properties: date and datetime.
The difference is:
- Datetime properties can store a timestamp at the date and time level. For example it is possible to use the APIs to update a contact property and set the datetime value to Feb 2 2016 at 5:04:13pm.
- Date properties can only store the timestamp at the date level, so you can only set the value to Feb 2 2016 not including the time.
Any Date Picker property you create in the HubSpot app is created as a date property. It is only possible to create datetime properties via API.
It is not possible to copy values from datetime properties to date properties in a Workflow because the date properties can't store the same timestamp stored in the datetime property. Date properties can only store the timestamp to the date, not the time.