Did you have it at 50 degrees the whole time, or after you finished fermentation? Regardless, you don't need to lager ales. 50 degrees is fermentation temperature for lager yeasts, with 34 degrees or so being the temperature you lager at. If you used ale yeast, you should ferment at around 66-68 degrees until done. 50 degrees really isn't a good temperature for storage or for lagering, though.
If it's not done fermenting, just bring it to room temperature and leave it. If it's done, you can bottle it.
You can always "cold condition" ales, too, but I usually do that in the bottle after they are carbed up.