"When did Iranians arrive in Lebanon?
They have been there for many, many months
though you won't know this
if you get your news from the MSM."
I've been flipping through the channels, so I can't recall who said it....NBC, I think...But, the reported that the Iranians have been flying 747's into Lebanon on a regular basis full of munitions and supplies for some time. That's why the Beirut airport went bye-bye first, to make sure there was no resupply possible.
See also #473.
Obviously the Iranians would not just leave the missiles at the airport and fly back to Iran.
Hezbollah would need 'advisors' for the installation and training.