Should I renew my PMP early?

Yes, there is no downside to renewing early. It is especially useful if you have a membership that is expiring.

Why put off tomorrow what you can do today? Waiting never helps – Don’t Let Your PMP® Certification expire when you have the option to earn up to 60 PDUs in an absolutely convenient and cost-effective way!

The time saved by doing it early can be used for another certification. Renew early and save your effort to spend your precious time at the last moment.

What if PMI makes a change in the PDU skill category or adds another one, All your effort will go in vain.

You can get it out of the way and can plan your finances.

Also, Benefit for the people who are PMI Members –

When you take membership for the first time and after appearing at PMP, if you get a pass then within the same year you can earn more PDUs by PMI earn PDU program and after earning 60 PDUs, you can renew your certification in the same year which will be valid for next 3 years from the end date of your current certification.
The benefit here is you save $90 since PMI members have discounted renewal prices.