Iran has a place to keep missiles secure until they are ready to launch:
Iranian state television broadcast new footage from inside an underground base on 14 October that raised questions about the scale of the facility and the concept of operations adopted by ballistic missile forces.
The footage was clearly intended to give the impression of a vast underground complex that contains a multitude of transporter-erector-launchers (TELs) that are ready to fire ballistic missiles. The Iranian report described the base as "a city which is beyond the enemy's imagination". Most of the missiles carried by the TELs appeared to be liquid-fuel Shahab-3-series weapons designed to target Israel.
Or maybe this is a dog and pony show--for now.
This cave/TEL concept certainly fits with the North Korean practice.
I wonder what else the North Koreans are doing for Iran?
Yet I have full confidence that the Possible Pretending Dimensions of our Iran policy can match any questions about the Possible Military Dimensions of Iran's nuclear programs.