Shardul,
The only way to "synchronize" your certifications is for you to wait until June 2016 and schedule your PMI-ACP exam on exactly the same day as your PMP Exam. But frankly, there isn't really much point in doing that. You cannot renew a certification "early" because it is always based on the day on which you passed the exam.
The more realistic approach is this:
- Take your PMI-ACP exam in October, and pass it...

- Now you need 30 "Agile" PDUs for your PMI-ACP recertification in 3 years.
- So start earning PDUs and focus FIRST on "Agile PDUs".
- Each Agile PDU that you earn will AUTOMATICALLY also count towards your PMP certification.
- And because they count twice, it means that once you have earned 30 "Agile PDUs" you only need 30 "PMP PDUs"
So first earn 30 Agile PDUs (they count for both certifications) and then finish off by earning 30 "normal" PDUs.
I answered a similar question (about PMI-RMP) in this post here:
www.project-management-prepcast.com/kune...to-renew-pmp-pmi-rmp
-- please take a look because the same approach works for you and PMI-ACP.