The 6 rows you have done sets the pattern for your lace so you will continue to keep repeating these 6 rows over and over even though you might be counting a different set of rows at the same time.
The next part asks you to work 30 rows so you will be counting these as rows 1 to 6 to keep your lace repeat pattern going but will ALSO count 1 through to 30 for this part of the instruction
The 30 rows have their own instructions for increases which are in addition to any instruction in the 6 row pattern repeat.
Youve done 6 rows now count again from row 1
Do row 1 of your 6 pattern rows which is also row 1 of your 30 rows (this has no extra increase, 39 stitches)
Row 2 of your 6 pattern rows is also row 2 of your 30 rows (no increase)
Row 3 of your 6 pattern rows is row 3 of your 30. On this row you get to the 3rd row of your 30 so it’s an increase row whether or not your 6 pattern rows said to increase. Think of it almost a 2 different instructions.
Row 3 increases because in the instruction for the 30 rows it says to increase on the 3rd row (and foll 10th) after putting an increase, then turn to your 6 row pattern and work the 39 stitches as described, for your size Inc 0, k2, you still do this it’s just you do it AFTER you have pit an increasenin due to the 30 row instruction.
Having an instruction to Inc 0 times on a row where elsewhere you are told to increase on the 3rd row is somewhat confusing. But its only this once that you put the increase in, its not part of your 6 row pattern repeat.
After row 6
Row 7 of 30 is row 1 of 6 pattern rows
Row 8 of 30 is row 2 of 6 patterns rows
Row 9 of 30 is row 3 of 6 pattern rows
Row 10 of 30 is row 4 of 6
Row 11 of 30 is row 5 of 6
Row 12 of 30 is row 6 of 6
Row 13 of 30 IS INCREASE ROW (this is the foll 10th after previous inc) and it is row 1 of 6
Please excuse the bit of Upper case text above I don’t mean to shout, but do want to point out where the next increase comes.
Not sure if this helps to clear it up?