Are there other ways to set varying contract expiration notifications?

Summary:

Contract Expiration Notifications Depending on Contract Duration

Content (please ensure you mask any confidential information):

Our client wants to be notified of expiring contracts. If the contracts have a duration of 3 years and above, they want to be notified 12 months before expiration. Meanwhile, if the contracts have a duration of less than 3 years, they want to be notified 6 months prior. 

Besides creating separate Contract Types per time of notification, are there any other ways to achieve this?

Version (include the version you are using, if applicable):

23C

Code Snippet (add any code snippets that support your topic, if applicable):