Actually, WP Travel version 4 provides the ‘Switch to V4’ option so that users who are using WP Travel plugin with the previous version(before 4) can switch to version 4 or can stay with the same version(they have used) even after updating WP Travel to version 4.
If a user who is using the previous version(before 4) of the WP Travel plugin wants to move to version 4 then they have to enable the ‘Switch to V4’ option by going to Admin Panel > WP Travel > Settings > General.

When we enable the ‘Switch to V4’ option to update WP Travel from the previous version to the v4 version, the database should be updated. So, you will get a message regarding the database update.

To update the database, please deactivate and reactivate WP Travel plugin.
Note: Please keep the backup before applying action as mentioned above as a safe side.
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