I have a website with 2000 users. I need to link my website with Adobe ACS throught the REST API.

Before testing or implementing that, I read the documentation and I have several questions about the documentation https://docs.campaign.adobe.com/doc/standard/en/api/ACS_API.html#introduction

Each user will be create one by one by calling the CREATE method. But each night, I need to update data of all users and send the changes to ACS.

Do I need to call 2000 times the PATCH method for each user or is there a way to pass a list of users data to update with an unique request ?

Can we use the method CREATE in order to update the data of an user if he is already known by ACS (from is email, id ?) or have I to send a GET request to know if my users already exist in ACS and after that make a CREATE or a PATCH ?

Thank you