Correct, the Plus trim level was introduced after the 2010 model year. In 2010, there were three R/T trim levels identified with factory ordering package codes "F", "J", or "M". The basic "F" package had standard cloth interior trim (leather trim not optional), standard 18" wheels, or optional 20" chrome-clad wheels. The mid level "J" package came standard with leather interior trim, standard 18" wheels or 20" chrome-clad wheels. The high end "M" is the Classic package and came standard with leather interior trim, 20" mag style wheels, 1971 style double side stripes and scripted fender-mounted "Challenger" emblems.
Your side stripes and "R/T" fender emblems are Mopar aftermarket items. I think I see a hood graphic which would not be factory original. I can't tell the interior trim. Cloth interior / 18" wheel combo means your car has the "F" package; leather interior / 18" wheel combo means "J".