Long lead items are just about everything these days in the O&G...

Long lead items are just about everything these days in the O&G sector. Vessels and pipe fittings,  the big things are not so bad and makes it look like things are progressing,  but it's the small things that can be mind blowing how long it takes to obtain. Control valves, safety valves, instruments, of which this small plant will have many can have leads times that are eye watering. If unexpected or blown out lead times is the main contributing factor to the delay, I wouldn't be surprised one bit. At least they will gain some experience for next time.
The below quote comes to mind.

'Experience is what you get when you didn't get what you wanted' Randy Pausch