Anyone having this problem: for now, the easiest way to get around this is to deregister Divi’s custom date scripts, like so:
add_action( 'admin_enqueue_scripts', 'slimline_remove_divi_date_scripts', 100 );
function slimline_remove_divi_date_scripts() {
wp_deregister_script( 'et_pb_admin_date_addon_js' );
wp_deregister_script( 'et_pb_admin_date_js' );
}
I only did this within the last hour so I haven’t seen if there are any problems in Divi after doing this. So far it looks okay, and the Divi timepickers look like they’re still working.