PETE COMMENT
I've been collecting the information on this major surprise. See the 3 previous Submarine Matter's articles.
I'm just beginning to present thoughts/comments.
First, in April 2016, the Australian Federal Government prematurely, but before the July 2016 Federal Election, chose Naval Group/DCNS to build the Attack class conventionally propelled subs. This was, in part, to gain votes/seats in South Australia (where Australia was to build the subs). But this premature Aus Gov announcement and action led to an unmanageable situation with Naval Group.
Second. Now in 2021, prior to the Federal Election probably in 2022, Morrison has announced a very un-nailed down "vision"to build nuclear propelled subs, again in South Australia. Everything is up for consultation with, not one, but two countries, the UK and US. To be cynical is fully justified that escaping the Naval Group unmanageable situation may lead to something worse. But rest assured votes and seats in South Australia (where these nuclear subs are meant to be built) are (almost) assured for Morrison's Government (which is behind in the polls).
An Australian nuclear submarine (Aus SSN) may become an even more unmanageable situation.
UNCERTAIN VISIONS/OPTIONS
This side of the 2022? Federal Election Morrison merely says Australia will build the SSNs, in Adelaide, South Australia.
It is possible the Aus SSNs will have traits of the UK's Astute class SSN and US Virginia class SSN.
A. If the Aus SSN is tailor-made for the RAN this will be very economically and technically risky, extremely expensive and may only produce a mature SSN by the late 2030s, if not later.
B. If Australia, instead, buys UK made Astutes or US made Virginias one of these SSNs may be delivered to Australia by the late 2020s.
OR
3. An Australian made Astute or Virginia may be ready by the early 2030s.