Have you actually had her out on shoots? Has she been trained to hunt under control? What does she do when she flushes birds, does she chase them then? Is she trained to the stop whistle? I agree that you need to go right back to basics on her recall, stop and steadiness and she must never be allowed to run off after birds again, you have to stop her having the chance to do this at all costs. I would also never let a dog which is unsteady to flush have the retrieve as this is a reward for it.
How old was she when first introduced to live game? Did you do steadying work with her in the pheasant pens during her training? I can't say enough that it's vital that she no longer gets the opportunity to chase birds out of control or to run off on you because once this habit is ingrained it's very difficult to overcome and you cannot take a dog which chases birds out on a shoot, it's both disruptive and dangerous, most gamekeepers just wouldn't allow the dog there.
If it were me I would start working on her stop whistle and her recall in a variety of situations until both were rock solid. On normal walks she'd be on lead if there's any chance of her putting up birds because harsh as it is she can't be given any chance to take off and ignore you or you're back to square one - if she does get this chance and she takes off and ignores the stop or recall whistle (and they get ONE chance only to obey) then I'd be after her - chase her, catch her and bring her back to where she was when she ignored the whistle and you must do this every single time. The aim though is not to have to do this because she never gets the chance to bog off in the first place while you're working on her steadiness.
My two older dogs are fully trained and the furthest they get from me when hunting in a training/working situation is about 10-15 yards; for my 7 month old who is currently in training it's about 5-7 yards. There's no need for them to go any further when working unless I've sent them out for a retrieve.
