是你要先申请600进入澳洲，并且这个600上面要没有8503，亦即允许你在澳洲期间申请第二个签证。在这个前提下，你可以递交804，然后获得一个过桥签（A），有这个过桥签可以一直停留在澳洲到签证批下来（或者拒绝）
If you apply for this visa in Australia, you would be able to get a Bridging visa that allows you to stay in the country lawfully while your application is processed. If you are given a Bridging visa A, you can apply for Bridging visa B to travel outside Australia while you wait for a decision.
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