Firstly many thanks to Viv & David and to Cepe (PG!) for their kind comments about my assistance in 405 matters.
As usual, a disclaimer! I make comments on here as an amateur, just someone who was one of the first to go through the 405 process (I think our application was about the 8th that was received by DIAC), and someone who reads all the small print. Anything I write on here is factual in that I have experienced it myself or have been told it by DIAC. If I state something about which I am not sure I will clearly qualify the statement.
As far as the timescale for medicals is concerned, our letter asking us to get the medicals said "Please provide the above information by . If you are unable to undertake your medicals by the deadline for any reason, ". No - that is not a typo by me, There was in fact no date shown after the word "by"! So I can't confirm the 49 days. If you have not yet done the police checks, bear in mind that in the UK the standard time is 40 days, and that is exactly what ours took. We organised ours while we were waiting for WA sponsorship, and submitted them with our initial application to DIAC.
The only issue here is that both medical and police checks are only valid for 12 months, so you need to be reasonably comfortable that you will get your visa within that time if you decide to get them done early.
Once the visa has been issued there is no date by which you must enter Australia - and as Cepe says, you are wasting some of the Second Visa Application Charge if you delay your arrival!
You are correct about the WA State Sponsorship being valid for 6 months, so you can submit your aplication to DIAC anytime within that 6 months. Perhaps Cepe is getting confused with the 3 months that applies to your financial information. When you submit your statements of current assets to DIAC they must all relate to a common date which must be within three months of the date that DIAC receive the application.
Cepe - you must get your visa stamped in your passports before you can arrive in Australia. We sent our passports to the Australian office in London using the Royal Mail Silver Envelope system, and got them back within 48 hours.
Cepe - when you apply to WA for sponsorship you have to state whether or not you intend to live in a regional area, and to identify the Post Code of the town you want to live in.
When they send the Sponsorship form to you, item 10 says "Has the applicant indicated that they intend to live in a regional/low growth area of Australia (as determined by the SIR visa definition of a regional/low growth area)?" The boxes below show Yes or No.
Item 11 says "Please list the Australian post code of intended residence" - and in our case this says 6210, which is the Post Code for Mandurah.
When we visited the Small Business Office in Perth when doing our research before we decided to apply for the visa, I asked what would happen if we had put 6210 and then found when we got here that we wanted to live slightly further out from Madurah - say 6208 (South Yunderup)? The answer was that so long as it was still regional it was OK.
In my view (note - opinion only!) then if you decided you actually wanted to be in a non-regional area after you had submitted the application to DIAC, it would invalidate your sponsorship and you would have to start all over again.
Hope all this is useful!
Regards,
Howard