The short answers to your questions: No. Maybe.
The not-so-easy fix: create a new I/O Unit, then move the points from the old one to the new one. There’s a “Move To…” button in the “Configure I/O Points” dialog which will let you move one point at a time to a different I/O Unit.
Does it matter? Not so much the way you went since the -R1 has MORE features than the -R2 (like high-speed digital counting). That’s why if you’d had the opposite situation it’d be more important. In other words, if you’d configured it as an -R2, even though it was really and -R1, and needed some of those features only available on an -R1, you’d be wondering why those were not showing up as options in PAC Control config.
Downsides to leaving it configured in your strategy as an -R1 even though it’s really an -R2:
The mismatch it could be confusing to someone trying to figure it out later. Also, PAC Control will let you add commands in your strategy for those points that the -R2 doesn’t actually support (rather than filtering them out – not showing features the -R2 doesn’t do).
On the other hand, if you ever decide you NEED some of those features, you can easily swap out your -R2 for that -R1 and not have to move the points over again.