Schedule reccuring page update.

Have you considered creating two posts and then setting up a custom redirect based on a custom value in the wp_options table that changes every week?
That would be a great deal simpler (and create MUCH less of a mess in your mySQL database with all the revisions) than trying to schedule alternating content in the same post.

You would create a plugin
(read this: https://wordpress.org/support/article/must-use-plugins/)
in Notepad++ or similar (just save as .php extension).
You would need to read this: https://developer.wordpress.org/plugins/plugin-basics/header-requirements/

You would use something like this
https://developer.wordpress.org/reference/functions/is_page/
to determine if the schedule is being requested
and then something like this
https://developer.wordpress.org/reference/functions/get_option/
to determine if it is currently week A or week B
and then something like this
https://developer.wordpress.org/reference/functions/wp_redirect/
to send it to version A or version B.

You would either have to change the option value from A to B (0 and 1 are better) every week using something like this https://developer.wordpress.org/reference/functions/update_option/,
or you would add the above to something like this
https://developer.wordpress.org/reference/functions/wp_cron/ which would enable it to happen more automatically.