Is there a stall with Turkey?

I'm currently 3 hours into a 22lb turkey smoke.  My plan was to smoke at 230 degrees for a couple hours, and then crank it up to 325 degrees to finish it off.  Well, 3 hours in the breast and thigh are at 138 and 139 degrees.  I was estimating 30 minutes per pound, but after three hours I'm a little worried it's going to finish way to early.  I have not cranked it up to 325 yet out of fear that it's going to finish well before dinner time.  Should I expect a stall?  Any advice would be much appreciated!