I’ve never been to Australia, and don’t know their immigration law, but I was born in USA but have travelled significantly in South America; in these travels I have acquired permanent residency in Chile and several types of visa in Peru, Argentina and Bolivia.
In my experience, when you (as an immigrant) acquire a new visa in your receiving country, your old visas will be annulled, usually with an obvious stamp in the passport page where the old visa was, or, if the certificate of the visa is separate, on the certificate page.
One reason for this is that different visas have different associated responsibilities and/or privileges. For example, on your first entry to a country you may be granted a tourist visa, but not allowed to work for pay. When you later obtain a visa allowing you to work, and perhaps stay for a longer time period, you will be treated according to the terms of the new visa, not the old. If the tourist visa were not annulled, you would be trespassing its terms. On the other hand, when a temporary residence visa expires, your privileges may be revoked, and you will be obliged to renew your tourist status, and will again be bound by those terms.
I am not a migration agent and this is not migration advice. Section 82(2) and 82(2AA) of the Migration Act of 1958 read (emphasis mine)
(2) A substantive visa held by a non‑citizen ceases to be in effect
if another substantive visa (other than a special purpose visa) for
the non‑citizen comes into effect.(2AA) Despite subsection (2):
(a) a maritime crew visa held by a non‑citizen does not cease to be
in effect if a substantive visa for the non‑citizen that is of a class
specified by the Minister, by legislative instrument, for the purposes
of this subsection comes into effect; and(b) a substantive visa held by a non‑citizen that is of a class
specified by the Minister, by legislative instrument, for the purposes
of this subsection does not cease to be in effect if a maritime crew
visa for the non‑citizen comes into effect.
‘Substantive visa’ is defined in Section 5 which reads:
substantive visa means a visa other than:
(a) a bridging visa; or
(b) a criminal justice visa; or
(c) an enforcement visa.
The text of the Act may be found here
Credit:stackoverflow.com‘