Hello @shreyashp 

Typically, I would recommend looking at the Certification page for information on the material for the latest exam:
https://www.databricks.com/learn/certification/data-engineer-professional

However, like you identified, there are some changes ongoing at the moment. I do believe they are currently revamping the certification, so depending on when you were expecting to sit the exam, you may want to look at the new specification instead of the old one. The Beta exam is scheduled from 28th August to 8th September, so I presume the old material is still live, but I don't know how long this will remain the case. 

 @ilir_nuredini made a post about the new exam here, with a pdf prep guide attached:
https://community.databricks.com/t5/certifications/new-databricks-data-engineer-professional-exam/td...

My guess is that the new material could be subject to slight change, as it still seems to be in Beta, but there are certainly some differences compared with the current prep guide.

I hope this helps.

Regards - Pilsner