As of my last knowledge update, the deadline for linking PAN and Aadhaar was extended multiple times in the past. The last known deadline was June 30, 2021. However, please note that this information may be outdated, and I recommend verifying the current deadline by checking official government sources, such as the Income Tax Department or the Unique Identification Authority of India (UIDAI) websites, or by contacting relevant authorities directly. They will be able to provide you with the most accurate and up-to-date information regarding the PAN-Aadhaar linking deadline