usef jumper tables vs ???? (easy question)

so i’m studying the jumper tables - usef. But noticing that some people refer to the different rules as Table a, b, c while usef only uses Table 2 through 4. (no Table A’s or B’s etc)

And one document i’m reading says “table A” and parenthetically (usef : Table II, section 2 ).

So what organization uses …or where did the Table A, B, C come from?

There’s sections a, b, etc. for table 2 (and possibly others?).

Table 2 sec 2A, for example, is the format for most big jumper classes.

no, these are just table A table B and table c, with those being the main titles. Wondering if it’s a ushja, not usef thing.