Writing your lessons learned will earn you zero (0) PDUs. It is not a qualifying activity for PDUs. However, please remember how the lessons learned from other people have helped you in your own preparation. So don't do it for the PDUs. Do it to help those who are currently studying!
Training for Project Management Professional (PMP)®, PMI Agile Certified Practitioner (PMI-ACP)®, and Certified Associate in Project Management (CAPM)®