Hi there!
I'm a first-timer so please excuse if I don't hit the tone right :P
I agree with you in that it looks like a hawk moth but I don't think it's a pine or a privet. Did you see the spikes on the ?femur? ? Neither pine nor privet hawk moth seem to have those features. Plus, I have not seen any images of either of the two speices with their antennae 'retracted' whereas the moth in our picture shows no antennae from top view at all.
Check out this website for Sphinx Hawk Moths:
http://tdserver1.fnal.gov/peterson/tom/Moths/Sphingidae/Sphingidae.html
they have many pretty pictures
I think your moth here may be a Ceratomia species, potentially a four horned sphinx... or closely related to it
I hope I spotted something there ;)
a wonderful day to you all
xj