ADRAP was an assessment delivered by Microsoft Premier Field Engineers (Microsoft employees only) through a Premier Support contract.
The Premier Field Engineers (PFE) became Customer Engineers (CE) and later Cloud Solution Architect - Engineering (CSA-E).
Premier Support contracts was replaced by the Unified Support contract. The Active Directory On-demand Assessment is included in the Unified Support contract. From a technical scope's perspective, it is a replacement and an updated version of the AD assessment.
I would strongly encourage you to connect with your Customer Success Account Manager (CSAM) which should be assigned to you (assuming you have a Unified support contract as you are asking the question).
More info: [https://learn.microsoft.com/en-us/services-hub/health/getting-started-ad