Using session cookies to serve landing pages to specific users

I need to be able to display (for instance) phone number A to visitors who come the site through landing page 1, and phone number B to visitors coming in from landing page 2. I’m in the very early stages of trying to think this through in terms of implementation and I’m wondering whether anyone has used this plugin to implement a similar functionality. The landing pages are going to be just regular WP pages – with front end enhancements.

These phone numbers can be on the header or if necessary they can be added as custom fields.

The goal is to be able to display a specific phone number for users as they browse the site – based on how they got to it in the first place. Any ideas and tips are greatly appreciated.

Thanks

https://wordpress.org/plugins/wp-session-manager/