I do that all the time. But I never dryhop more than about 7-10 days at the most. I just add the dryhops about 3-7 days before packaging. The dryhops will give up their goodness in just a few days at room temperature, so there is no advantage to dryhopping for longer and you may risk some grassy flavors from a prolonged dryhopping.
Broken Leg Brewery
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