Please let me know if correct.
The basic formula for each stamp in PF's database is this:
1st: COUNTRY OF ORIGIN
2nd: The submitter's personal assessment
3rd: The final verdict according to the PF
Also apparent:
The Scott number (written in by the submitter) does not change, even if the PF deems it to be something else.
For example, if you search for a Scott # 63a in the database, they will show you a list of both 63a's that they deemed to be GENUINE, and stamps labeled 63a by the submitter that weren't given the "a" variety by the PF.
It would look like this:

I asked a question recently on here about whether or not the PF will specify a stamp's variety even if the submitter failed to label it as such.
According to the formula used in this database, it should be easy to find the answer by simply locating a verdict that would resemble the following:
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63 1861 1c blue
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AND WE ARE OF THE OPINION THAT IT IS NOT A 63, RATHER, IT IS A 63a, ULTRAMARINE*********
Or...
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157 1873 2c brown
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AND WE ARE OF THE OPINION THAT IT IS NOT A 157, RATHER, IT IS A 157a, ON DOUBLE PAPER*********
I searched through hundreds of pages of #63 and hundreds of pages of Bank Note issues. There were many submissions that claimed to be varieties in color, paper type, double impressions etc. which were 'knocked down' by the PF, but none like the two examples I typed above.
It's not like they wouldn't know, as they go to great lengths in mentioning even the slightest crease or tear. They are examining each piece very closely, and should be able to recognize most varieties without any extensive lab work.
Here are two "dot in U" 63 varieties:


One was prelabeled as such by the submitter, the other wasn't. In fact, every "dot in U" I found (which are very easy for anybody to find from a picture) that wasn't labeled as such by the submitter did not have the variety included on its certificate.
So I would like your opinions on this, or if you could provide a picture that shows a variety being included that adds value to what the submitter originally requested, it would be very helpful.