仔细看了看,觉得你说得正确。
那个who是特指temporary resident:..., or a temporary resident who has lived in Canada for the previous 18 months, and who has a valid permit in the 19th month.
那个逗号不应该用,应该是:..., or a temporary resident who has lived in Canada for the previous 18 months(,) and who has a valid permit in the 19th month.