I don't fully understand your question because all squadrons have to be given orders irrespective of whether they are pinned in close combat or not. As such, you would be issuing orders to an entire squadron not just individual stands. I can only assume that you are asking whether it is allowed to issue first fire orders to a squad that has some stands which are pinned and others which are not? If this is your question, the answer is yes, but remember that only those stands which are not pinned would be able to fire (first fire can only be used against those models in close combat on the turn in which they charge).
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SoƱando con una playa donde brilla el sol, un arco iris ilumina el cielo, y el mar espejea iridescentemente.