Swarf - back rib 2x2

I am working the Swarf and need some help with the start of the back.
Pattern reads
Co 52 Beg 2x2 rib; work even in pattern
It doesn’t say how many rows for rib and btw there was no rib on front so don’t think there an a rib
The pattern across the row sb multiples of 16 stitches. Knit 16 purl 16 knit 16 leaves 4 stiches
Are these worked in rib all the way up the side of the back.
Thanks for any assistance

I wish I knew! Rather frustrated with the poor writing. With only four extra stitches total, that would be a rib on each side would have to be 1x1.

The knit 2, purl 2 rib is a multiple of 4, as is the direction for the rib pattern.
It is sequential, just as the front begins - every row is the same.
The directions ask you to follow the marl table, 40 rows with the first combination of yarns, then 8 more with the second.