@Roo I think Iran is on it's last leg.
It's strategy now is simply to choke Strait of Hormuz to not let any oil/gas pass and attack Gulf countries commerical infrastructure, to pressure the world to intervene to stop Israel and US. It will end war and Iran will claim they successfully defended against USA and won. Face saving act but it come across as Iran has no other options. It's on last leg.
If US and Israel stays adamant and continue the strikes like yesterday (400+), I think within next 7-10 days or so, Iran would totally be down.
Iran's hope that World will intervene might not work as quickly as Iran thinks- All major countries have oil reserves (China - 3 months reserve, India - 2 months with importing more from Russia, Europe - 60 - 90 days, Canada - exporter, US - few months, Russia - Exporter)
As these countries have sufficient oil reserves so they might not intervene as quickly as Iran anticpates.
But countries lacking reserves might see partial shutdown of their economy.
So, I feel global intervention is necessary as quickly as possible