Unless I run out of eels, I always go to my assigned area and wait atleast two days for action.
If nothing appears and experience leads me to believe it won't, I move on.
My favorite areas are AM 52 and AM 53.
I also like CG 86 area.
On the first patrol of the war-I go for the St. George's channel-I think AM 97.
Afrika has always been a bust for me.