The two dots are found under the letters RN of BERN in BERNARDINO.
I find two specimens with this plate variety, recently reported by Rein. The two I find are different positions in the plate, as are the two from the position immeditely right of this plate variety. Here are comparisons of the 'two dots' specimens;
and of the position to the right of the two examples on hand:
Here is the strip of three with the first example.
Middle stamp, 'two dots' (shown at top)
top detail of the right-most stamp
bottom detail of the right-most stamp
The second specimen is found top left in this block.
Top left, 'two dots' plate variety
Block labeled for types (2 is II, 3 is III):