We have a different number of tickets on different days. How to configure that?

Add another rule to the resource. Read how to do this here.

Now you have two rules. Decide which of them should have a different number of tickets. Open the settings form of this rule and specify a required Total share count value.

Then click on the intersection of this rule and a price option. In the form opened, specify a desired Share count for the price option.

You will get this configuration:

See this example in action: