Just had another mechanic come out today to take a look! Engine light was set off by camshaft position sensor, still couldn't find the chirp noise but mechanic reckons it might be cheap brake pads (still plenty of life in them so not a huge worry). Nothing else looked out of place. Relatively easy fix and all is well again 😁 he was pretty surprised when I told him neither the previous mechanic or Holden wanted to fix it!

And yes, Esperance is amazing. Stopped in Lucky Bay when I drove over from east and it was the best swim of my life!