2c Wright (Scott 1280) Question

I was looking at Scott catalog and checked Durland.

There is one sheet version and 4 booklet versions
1280 sheet
1280a pane of 5 with two different slogans (2 varieties)
1280c pane of 6 shiny gum
1280c pane of 6 dull gum

1st question: Scott shows a dull gum from booklet between 1280 and 1280a. I am not sure this is the single from the dull version of 1280. True?

2nd question: It is not stated but assume 1280a is a shin1y gum since that was the norm. True?

3rd question: Can you tell the difference between booklet singles removed from the pane other than shiny gum?

#2 1280a (pane of 5) is shiny gum, 1280c (pane of 5) comes both ways.

#3. No way to tell individual stamps w/o gum apart as the gum is the only difference.

Thanks for confirming.