Thanks for the comment,. Leaving it in the UK is an option though I'd like to take advantage of the 6 month tax window and keep all my pension arrangements as simple as possible.
I don't know my tax calculation is correct. A 45% tax on any amount over $AUS 300,000 seems prohibitive.
"Jun 10, 2019 - If you transfer your UK pension to an Australian one within six months of moving to Australia, then you can do so without any tax implications. If, however, you don't make the transfer until after that period, the amount you transfer will be subject to a 15% tax, according to the Australian Tax Office, or ATO."