Hello.
Unfortunately, by default it’s does not possible.
You can make your own customization (but it’s only on your own risk, it’s will not be supported in the future updates).
Please open this file ../wp-content/plugins/booking/js/datepick/jquery.datepick.wpbc.5.6.js
( you can check how to edit files in WordPress menu in this article https://wpbookingcalendar.com/faq/how-edit-file-in-wp-menu/ )
then find this code:
monthNames: ['January','February','March','April','May','June',
'July','August','September','October','November','December'], // Names of months for drop-down and formatting
and replace it to this code:
monthNames: ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'], // Names of months for drop-down and formatting
Disclaimer. Unfortunately we can not start, right now, some personal customization or custom development, because we have almost no free time.
Check more about, what support we are providing here https://wpbookingcalendar.com/faq/what-support-do-you-provide/
Thank you for understanding.
Please note, if you modify the source code of the Booking Calendar, we will not guarantee the correct work of the plugin and do not support it.