justhavingalook, you'll need to be a bit more specific. 1200hours is the highest houred inspection, so do you mean 4800hours? Or 2 year, 4 year, or something else?
Globally, the highest houred 139's are in Den Helder, Netherlands, and they are closing in on the 4800 hour inspections pretty quick.
Avionics wise the 1200 has a few checks to do, as does the 600 and 300. Nothing too big. Every 4800 hours there are some circuit breakes that need to have an operational check performed. I didn't look into it too closely as none of the 139's where I work are anywhere near 4800 hours
Send me a PM if you need details of inspections, I'm always interested in news from the motherland (Aotearoa).