completed and completedDate
A special note about these two properties in the Person Task API: The completed value is treated as the master property. Setting this value to anything it is not currently at will reset completedDate as appropriate. completedDate can be set to a date which will trigger completed to be true. However, after saving a Task, changing the completedDate to null will not reset completed to false. This only applies to changes to existing tasks.
Get All Tasks By Group
GET /ssp/api/1/person/{id}/task/group
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