The essay dies for this series did not have dots in the circles.
The reason I point this out is that is not always the case. There are two varieties of the 4 cent Parcel Post Stamp, one with a dot in the tail of the right "4" which is listed in French's plate variety encyclopedia but not in Scott, YET THE APPROVED DIE DESIGN was as such. The dot exists on the die and thus the die proofs, but was removed from some, but not all transfer rolls (used to make the printing plates). French does not list all the plate numbers for which the dot can be found. His listed plates all went to press after 1-1-1913. There is at least one more, I believe more but did not concern myself with recording any others for the reason following. I was and stopped looking for one particular example when I found a plate number that I needed to prove the dot existed on a plate which went to press prior to 1-1-1913. This was to show such stamps were available for use on 1-1-1913 first day of Parcel Post Service mailings.
Die essays used for the R228 et seq (Q12a-E1-Q12g-E1):
Die essays continued for the R228 et seq (Q12h-E1):
Approved Model (Currently, 2021, and oddly, not listed in Scott as an essay):
[EDIT: I forgot to mention this image is cut down from the actual full size of the model so I could meets posting size requirements]
While the photos are all from Siegel's Power Search, Sale 1094, lots 274 & 275, plus (middle illustration) lot 387 of sale 837. I own but have not photographed the 20 cent die essay. As shown, no dots on any value.
The types I and II are known used to pay the WWI parcel tax 11-2-1917 through 12-31-1921; wonderful usages to find, especially in combination with parcel post stamps (Good luck finding a "dot" Q4 with a type II documentary). The third type was not produced until 1924 as noted by revenuermd above and will not be found as a war tax use.