I was not 30 when I took my first practice test, so the age may play a factor here but was much better prepared than you. I scored 540.
4 months later I walked out of a test center with 750.
it is possible but there are factors in the way such as work load, family, distractions, and well.... age - being on your side of the 30's divider, I can see how it gets tougher and tougher to remember things.
So, yes, you can do it if you have time.
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