I can't speak for Cisco but usually if they change the blueprint of an exam, there's notice given, a grace period to take the old blueprint and the updated blueprint is posted publicly here: CCDE - Cisco
Until they update that to say there's a whole new blueprint, I think you're safe to study the same books.
As far as the rest, I'd probably open a case with Cert support and see where they can help you out there.
My name is Brent Morris and I’m the enforcements project manager for Cisco’s Certification program.
Due to irregularities found on the delivery of the CCDE(p), Cisco needed to make the appropriate adjustments. The adjustments are required and have resulted in rescheduling the exam to August 29th 2017. The adjustments will also result in a better testing experience for the customer. We truly understand the inconvenience of this decision and Cisco did not make this decision lightly. Please understand this decision was made for the greater good of the CCDE certification and the test taking experience for the customer. Unfortunately, Cisco will not be able to provide any additional details on why this decision was made. We (Cisco) hope that our candidates respect our decision and we wish everyone good luck on their next attempt on August 29th.
If you have any additional questions or concerns, please feel free to contact me directly at (email@example.com)
It created some inconvenience due to the last min cancellation, but as Cisco Official clarified above, there were irregularities found on the delivery so there was no option, but to cancel it. Other wise it would have been a repeat of Nov2016 and Feb2017........
Now that industry is is getting a more clearer picture of why Cisco has cancelled the May exam, there is overwhelming support for this decision, and a lot of Cisco professionals are appreciating the decision in forums/discussion boards etc.It was pretty clear from November 2016 because of the unusually high no of candidates passing the CCDE from certain country/region...A lot of professionals are hoping Cisco will take strict action against those responsible for undermining the credibility of CCDE.