I managed to find an extra iteration or two without sacrificing to much stability.
6.06 / 7.59 / 9.11
Running with Doggettx selected as the optimiser in the optimiser config inside automatic1111.
I installed the google perftools as suggested in this thread
"sudo apt install libgoogle-perftools-dev"
And then added the following memory management options as suggested in this thread
by exporting: "export PYTORCH_CUDA_ALLOC_CONF=garbage_collection_threshold:0.6,max_split_size_mb:128"
Made the following changes to my web-user.sh
Uncommented the command line options as follows: export COMMANDLINE_ARGS="--medvram --upcast-sampling"
And added the following lines to the end of the file