I'm not sure there is much you can do with the timeframe you have.
You could try to include a sprint bit at the end of sessions and consider if you're training enough days.
You might want to modify your diet, so improving bloodflow by not eating and drinking Caffeinated products would help, as Caffeine consticts bloodvessels and blocks Iron absorption, so reduced Erythrocyte, (Red blood cell), count, slower bloodflow and reduced Myoglobin production, (used as a storage mechanism for muscle Oxygen), could increase Lactic Acid production, because the body won't be able to breakdown as much Glycogen in the manner it would prefer to, because when Oxygen depletes and Glycogen is still being broken down, you'll get anaerobic respiration, one byproduct of which is Lactic Acid.
You could try to improve dilation of vessels, by increasing Protein intake, as the Amino Aicd Arginine stimulates Nitric Oxide production, to dilate bloodvessels as one of it's functions and more Protein in that case, would be more beneficial than just taking something like an NO2 supplement, which has a limited benefit.
Arginine supplements would be okay, unless you had a Herpes Virus, (not 100% certain about Zoster the shingles virus), as Arginine makes Herpes worse apparently, but Lysine can help to suppress it so I believe.
So I'd say if you need more dilation and therefore better bloodflow to the muscles, increase Protein if you think it will help, but definitely consider the option regarding Caffeinated drinks and foods and also Tannic Acid in tea blocks Iron, so it's a double whammy because of the Caffeine content as well.
These are things to consider, but you're still giving yourself just over a month to achieve the recution in running time, so don't expect to do it necessarily, because of the small timeframe.
Good luck

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Oh and perhaps consider if your Carbs are enough. You might be undereating them slightly depriving yourself of Glycogen stores you might need, as carbs breakdown into Glucose and then store as Glycogen in the Liver and muscles, but inadequate muscle Glycogen would be a hinderance to your running.
Plus the extra Oxygen content in the carb water levels, would be beneficial at staving off Lactic Acid production and as ATP, a primary source of energy for muscles, contains Oxygen, a preferable amount of Carbs helps there too.