Yes, D. maculata females occasionally have additional development on T-3, and rarely this may become almost a complete band. The one in the photograph is interesting because the additional development takes the form of small floating "dots". This all illustrates the value of observing as many specimens as possible to become familiar with the variation within each species so that you will be able to identify "freak" specimens where the keys simply don't fit!

By the way, some workers of this species in the eastern US may be as large as queens from the Rocky Mountains!

This can only be a bald-faced-hornet queen, even if a bit smallish.
I agree with Bug Eric that such a pattern is not common for this species, especially the two isolated white spot on the third abdominal tergite. But the first and second tergites remain wholly black, and D. maculata is the only species with this feature. A D.artica female would have a small white apical band (at most interrupted medially) on each of both of these segments, pure black (instead of chocolate-brown) compound eyes, and mainly black (instead of white) ocular sinuses.
It is interesting to compare this specimen with the other queen of this Guide (that one disturbed during overwintering in a rotten log), which comes from the South and has an entirely white pronotum - whereas the pronotum of this one looks more like a worker's.

That is one strange color pattern on your wasp there. You might want to investigate the possibility that this specimen is Dolichovespula arctica, rather than D. maculata.