If 90% of your job becomes automated via ai, you'll be able to handle 10x the number of jobs. That implies that there will be 1/10 the number of available positions for accountants. That's a big assumption. Perhaps there will be an accompanying boom in the economy that increases the need for accountants 10 fold. That seems optimistic, however. There are other limiting factors to economic growth that AI can't foreseeably overcome until ASI.

In the labor market, you'll be competing for fewer positions against a lot of other accountants. Salaries will decrease. Eventually, there will be fewer people becoming accountants. That isn't particularly helpful for you though. Those changes in the supply of accountants will take decades. The changes in the demand for accountants will not take nearly that long.

Look for competitive advantages that will ensure you can still get a job. Knowing how to effectively use AI for your job seems like an obvious one. Specializing in a very niche area of accounting may provide another as that specific knowledge base will need to be coupled with the more generalized abilities of AGI.