Ok good posts
Just to let you know why am not worried about Accuracy, for a start I do Prospecting looking for Gold/rocks & minerals as a hobby, I like to go out bush in Western Australia and look at my own country, have worked over seas but never done a Holiday trip. "why" anyway I have been mapping since 2000 and have converted all sort of files into geo co-ordinated maps and use them to go where I want to be. "That's what we want isn't it ?" so while I doing my mapping I use what ever co-ord system is avail on the software. No the Devices I use are older than GDA 2020 so hey not worried.
First device is:
Spoiler: pic1
013

I have 2 of these the latest software is V2.14 no further updates " so they are WG84"

I also have one these:
This device at the time was one one the series "Before In-car NAVS where introduce to cars."
So I was able to get My M8's in the area of interest better.
[Only registered and activated users can see links. ]
I used OziExploerCE for this and have used it since Beta version.
Only last year I update to a Tablet and a new phone to run a program called Trilobite Solutions which brings all my data into 1 program and I have been assisting the Developer with update to the program.
Spoiler: Pic3
Screenshot 20210102 084541 Australian geology travel maps 2

Accuracy in Geology is not guaranteed so hey who cares.

Not downing your need for info Eyelet99 just stating my facts.