Yeah, if I was in your shoes I'd try Entyvio next.
I hope you can get several more years remission from the remaining biologics. It must be frustrating to be doing well on a med, and then all of a sudden it stops working.
Dx Crohn's in summer of 2000. (Yay )
Tried and failed: 5-ASAs, azathioprine, 6MP, Remicade, methotrexate, Humira, various diets.
Had surgery Feb '13 - subtotal colectomy with end ileostomy. First thing to put me into remission in 13 years.
Had second surgery 10th July '15 to reverse the stoma and connect the ileum to the rectum. Officially flaring again. The fun never begins.