[support] make a controlled field independant of the controlling field via form alter

Hi, I have got a few conditional fields, say B & C controlled by the controlled by A. Now in some scenarios controlling field A auto selected and hidden (by setting '#type' to 'value') in hook_form_alter. With this B & C stay hidden too. I don't want this. I want B & C to be visible and editable by the user even though the controlling field A is hidden. How do I achieve this? cheers - Ben