The best advice is to use the time/pound as only a guide to estimate. For pulled pork, it's done when a probe thermometer or ice pick goes into the butt in a few places "like butter". In other words, with very little or no resistance. The internal temperature is usually between 195 and 205 from what I've seen. If you are slicing it instead of pulling/shredding it, it's done a little earlier.
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And now, brethren, I commend you to God, and to the word of his grace, which is able to build you up, and to give you an inheritance among all them which are sanctified. [Acts 20:32 KJV]