To check if any OEM is set up login to office 365 and then open this page.

https://businessstore.microsoft.com/en-us/manage/partners?invitation=true

To Setup Dell as the OEM for AutoPilo login to Office 365 and then copy link below to authorize Dell

https://businessstore.microsoft.com/en-us/manage/partner-invitation?invType=OEM&msppId=0&partnerId=4f087693-60fa-4082-be28-2fc6d116136b