For my money...
IF the F/O noticed the problem....immediately reach up over your head and select ALT FLAPS to ARM and then select DOWN..only takes a second...
That should both keep the LE devices extended, and stop any further retraction of the TE flaps...
Then when I get a second to spare...I could then select DOWN again to get enough TE flap to keep it flyin'.
But I seriously doubt that most FOs would notice...but then again, if we had a Flight Engineer aboard....he would be the man to do my bidding!
..with the 320, who knows where anything is at any particular moment...including the airplane itself!
that'll get 'um snarling....
Cheers...FD...