Kitchen sink sprayer

[EFH]

I am trying to change my kitchen sink sprayer, hose and all. I cannot get it disconnected underneath. I know I need to disengage that black piece, but I don't want to keep twisting and pulling without knowing how it disconnects. I have attached a picture taken from below and to the side. I would appreciate any help!

 

[Smooky]

I would try to pull that blue part to see if it is the release and then pull down on the hose.