So, the verse indicates that their circumstance has changed...

So, the verse indicates that their circumstance has changed to a state that if they see all the signs and revelations of Allah they will not believe in them. The verse says: "... and (even) if they see every sign they will not believe in it....." The verse informs the Prophet (S) implying that beyond their disbelief, when they come to you they have no aim but disputing and quarrelling with you. The verse says: "... So that when they come to you they dispute with you....."