within thirty days on expired visas as long as they possess a va

文中并没有定义a valid I-94 form "that is associated with the expired visa".

如果说成　within thirty days on an expired visas but with their valid I-94 forms.....那就说明I-94必须是跟visa stamp相关。

实际表述　as long as they possess a valid I-94 form，说明这个I-94不必要是visa stamp发的。