Function invocation quota limits for us-central1... deprecated?

Question

I was happy to learn I can set limits to my function invocations so I don't have to worry about billing. I tested it and it works (by setting the limit to 0). But:

1. Why does it say deprecated? I couldn't find documentation on this anywhere.
2. What's the alternative? Should I even be using this?

Answer 1

This was sent via email with the subject Some GCF Quotas will be removed on Sept 8, 2020

Some customers may have used quotas as a way to limit spending, e.g., either via the default quota limits or by lowering their quota. You should now be advised to use Cloud Billing Budgets or Max Instances to limit spending or usage.

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