I'm surprised nobody reply to you in such a long time. First two numbers represent the year the cue was started, so when it enters production. Then you should have an "I" or an "S" for Ivory and respectively for SS joints. The last 3 numbers represent a serial number. So actually the hole "thing" is the serial number. Ginacue model numbers should look like 12A, 13E, 11D, 14C or something of that nature, but this is not marked anywhere on the cue. Sometimes Ernie's cues even have names like "Black Sabbath" or "Rasputin".
Good Luck