usergroup auto action - assigning groups by zip code

Looking for a bit of help or a push in the proper direction:

I have a a bunch of user groups each with a list of zip codes that belong to them (territory). When a new user registers they should automatically be assigned to the group controlling their zip code.

Using the Usergroup Auto Action I've successfully been able to assign a new user to the correct group. The problem is I have only figured out how to use one zip code per action. Some of the groups only contain 5 zip codes which is manageable. Other groups have over 500 different zip codes assigned to them.

Is there a way to use the zip code to assign users to groups if it is included on a list of zip codes?/ Is it possible to include this zip code list in the conditional statement somehow?

You can use a REGEX operator in your condition to match multiple values. Example as follows.

[cb_zip] Is REGEX /^2000|1000|9999|3333$/

The above would match all 4 numbers.