California estimated tax payment

I am based in California. Here is my situation:

1. Worked on W2 in Jan and mid-Feb (taxes deducted as part of payroll)

2. Remained unemployed between mid-Feb and mid-Jul (collected unemployment)

3. Filed 2019 taxes in June using Turbotax Home & Business

4. Have undertaken couple of consulting jobs on 1099 from mid-July which is likely to continue till end of the year

How do I calculate my CA tax obligations for this year and should I be planning to make advance tax payments using 540ES on Sep 15? I know California usually expects no payments on Sep 15 - would that hold true even in my case since I started the consulting work only in July?

Appreciate any help or insights.

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