Hello Kyaw,
As always when it comes to earning PDUs, allow me to recommend that you always consult the official CCR Handbook at
www.pm-prepcast.com/ccrhandbook
. Now on to your questions:
PMI allows you to complete the renewal process as soon as you have reached 60 PDUs. They write "You can complete the renewal process at any point in your cycle after the PDU requirements have been met by submitting payment.". This, however, does not change the start and end date of your cycle. Your first three-year renewal cycle starts on the day you pass your exam. And the following cycles all start after every three years. Nothing changes this three-year "rhythm". So you can go ahead and earn/report 5 more PDUs and then complete the cycle. Now you can wait with earning any new PDUs until after 02 February 2020.
Also remember that if you decide to earn PDUs before the new cycle starts, that you can only 'roll over' a maximum of 20 PDUs to your new cycle. And you can only roll them over if they are earned in the final 12 months of your cycle. So if you complete your renewal cycle in the next few weeks, then you should wait with earning new PDUs until Feb 2019. Now you can start earning PDUs for your next cycle. Just don't earn more than 20 PDUs before 02 Feb 2020 because anything over the maximum "roll over" number will be lost.