Increase number of instances in Premium Plan
limit of 20 instances in Premium Plan sounds low. We have 800 dataflows in our custom solution.
I understand 20 comes from 288GB vm/14GB instance
But you may consider something like 'extended/virtual' plan
Then you could allocate multiple of 20s and for exemple in our case have 40 units of 20 instances = 800 in total
You are now able to scale up to 100 instances!
Azure Functions Team
Matt Conflitti commented
This does not seem to include Linux instances, which is still listed as having a limit of 20.