Now that I'm listening for the noise I can hear it first time starting i the morning and doesn't have to be when shifting into reverse or first although that is when i hear it most.
It doesn't happen again through the day when the car is warmed up.
it's like a loose bearing or idler chirping somewhere low and seemingly from the left side. Only there for the first half minute of so then goes away till I start it up again in the morning. it seems to be getting somewhat more pronounced or worse so would really like to catch it before it gets too bad or something fails.