You can move the bolts, using any of several methods. It looks to me like there is space to allow for a couple of washers. A 1/2"higher toilet is not a big deal.
Take the toilet bolts out and enlarge the holes. Get/make some big 3/16" thick washers and relocate the bolts. You can make it permanent by welding the washers to the plate, or by putting some small bolts through each washer to hold them in position.
If you want, you can weld up the holes and drill new ones.