Aadhaar PAN linking: Remove all confusions here; understand what Section 139AA of Income Tax Act says

There are lot number of queries over Aadhaar number-PAN card linking. What if one fails to do Aadhaar-PAN linking? What will happen after July 1? After the questions were raised after the government made it mandatory to link existing Aadhaar numbers with PAN of taxpayers with effect from July 1. Amending income tax rules and notifying the same, the government made quoting of the 12-digit biometric Aadhaar or the enrolment ID a must at the time of application of permanent account number (PAN). The revenue department said every person who has been allotted PAN as on July 1, 2017, and who in accordance with the provisions of sub-section (2) of section 139AA is required to intimate his Aadhaar number, shall intimate his Aadhaar number to the principal director general of income tax (systems) or DGIT (systems).