How to use collectionStrategies API to load Strategy/Tasks against Customer with user defined dates

Summary:

I'm using the /fscmRestApi/resources/11.13.18.05/collectionStrategies API to assign a Strategy to a Customer and setup the Task to be executed on the correct day. I can create the Strategy and create an Complete Task but the Start Date and End Date on the Collections Screen always show as sysdate/creation date. I can query the database to see the Schedule Start/End are what I have entered in the API body.

Am I missing a step?

Also, I am unable to get PostWaitEndTime to be recognized in the API. The API runs with 200 but the PostWaitEndDate always returns null in the Response.