There are no OEM versions of the Adobe Creative Suite or the applications therein. Various websites that offer such OEM versions of software, typically located in Eastern Europe, are using this as a ruse for offering illegal, pirated software.
(Note that this is not the same as buying a new computer with a pre-installed and paid for copy of an Adobe application - those applications are paid for and licensed just as a shrink-wrapped copy of an Adobe applications.)
Illegal, pirated software is obviously not upgradable and if you get caught with same, you face the same potential prosecution as anyone offering such counterfeit goods in the first place.
- Dov Isaacs, former Adobe Principal Scientist (April 30, 1990 - May 30, 2021)