Need some help with some basics ???

My Aadhaar card register phone number is different from my PAN card register phone number. I was not sure about whether my PAN card and Aadhaar card were linked earlier as I was in a doubt that maybe both the numbers are different, so the linking won’t be possible, but today I went to the UD ISL portal and check the status of linking and found out that my Aadhaar and pan card was linked. Now I am quite relief by the fact that both the cards have been linked . Q.1) what if I I don’t make changes in the phone number on my Aadhaar and my PAN card?? Q.2) will there be a problem in future while filing for ITR or opening a bank account etc. Q3) or shall I proceed with changing the pan card registered number as it is convenient and easy to change compare to Aadhaar card ?? Q4) if in case, I change the phone number on my PAN card, will I need to re-link again, my both cards ?? I dont know whether its the right sub or not. I apologise in advance