Sortable checkbox fields showing key names, not value

Dear Plugin AUthors,

As of version 3.5 of plugin, the sortable checkbox fields are not displaying label names. They show key names. For example, the following code:

'id'       => 'id-name',
'type'     => 'sortable',
'mode'     => 'checkbox',
'options'  => array(
    '1' => 'Item 1',
    '2' => 'Item 2',
    '3' => 'Item 3',
    '4' => 'Item 4',
)

outputs 1, 2, 3 and 4 inside Option Panel and not the label names. The 'mode' => 'text' is working correctly.

https://www.ads-software.com/plugins/redux-framework/