Yes, the districts changed names/numbers and I don't know the reason. My Millers lived in district 638 of Henry, GA circa 1825, later it was just 8th District [1830]. I found a land lot map online somewhere [can't recall url], but it was only for Henry, GA. Later, I bought a complete land lot map from their Historical Soc. I would guess the availability of these maps is dependent on each county, but you can try googling "land lot maps Georgia" and see if that brings up anything. If no luck, I'd contact the specific counties of interest. Also, they can probably explain about the district numbers changing - when, where, why.