My understanding of the H prefixing the serial number was Savage started using a letter for "dating" the rifles beginning in 1968 because of the GCA and the letter H was used on the Model 110 specifically from the years 2009 through 2013. The link I posted for you was for understanding the letters in the MODEL . I.E. "Savage 110 FXHD or some other "alphabet soup. Those letters would signify what that specific rifle sported. Such as flat back or round back, hardwood stock, trigger, things such as that. Thought maybe understanding those may help to nail down the rifle. Again, as far as the letter H heading the serial number, I don't believe they would us that in a different year group even for a special run since they were using the letters to identify year groups for GCA compliance or some thing along those lines.