With your TIA Portal  PID 2.x project open showing at least 1 logic block (I tend to open OB1 Main), now follow the steps in F1-Help when you search for this phrase:

TIA Portal F1-Help - Search for:

"Update program in the current PLC"

Open the search results title that exactly matches that search phrase and the procedure is provided.

Afterwards, the various differences will need to be addressed for each PID instance - unless you are very clever.

I doubt there are many (if any) people that clever, so if you go the simple route and address them all - like I do - then you are on the right path to success. 

If you try to be clever, you may be digging a deep hole you may never get out of nor reach the bottom.  Please don't take this as a slight nor as a challenge.  Just that I'm smarter than average and I try to imagine what the smarted PLC programmer would do and all I come up with is they would pull all their hair out and never admit defeat, but also never claim victory, and ultimately, lose their job.

samuelbb

How the update from 2.x to 3.x should be performed? Replacement of instances one by one?