Can anyone help me to answer this question?

My hu*****and is a F-1 student who filed 485 via NIW two years ago, then get denied about a year ago. Now he will file 485 with me because I will file 140 this time. Can anybody tell me whether my hu*****and's stay is illegal during the year after his 485 was denied? He is still a graduate student at school and will graduate early next year. Thanks much for your reply.