When trying to understand these communications, we have to consider why the author (or Zodiac) didn't just opt to paste the words on a postcard or greeting card in similar fashion to the '13 Hole' Postcard or Pines Card. In this instance he chose an astrology backdrop with dates for both communications, suggestive that the numerical dates were the key ingredient for the message to be understood. In a recent article we investigated the possibility that the Day-by-day forecast for Leo was in reference to the abduction and murder of Leona Roberts, hence why it was mailed at about the same time as her abduction on December 10th 1969. The same goes for the Day-by-day forecast for Cancer communication which I have added below.
If you take a quick peek at the Leo communication, you will notice that the pasted wording FLT Three of a Kind (meaning 555) also begins at the 9th of the month. Two phrases, FLT Three of a Kind and FLT 555, both beginning on the 9th. Is that really just accidental? This was the numerical day before the abduction of Leona Roberts. The connection is speculative at best, but we have to consider that the FLT (the common strand between both communications) having been placed next to this date twice, has some relevance to the 9th - and quite possibly the impending abduction date of Leona Roberts. Find, Locate and Target, or Find Leona at Tormey, akin to the acronym of BTK used by Dennis Rader several years later, is one possibility for this pasted section. However, there are multiple possibilities pertaining to the motivation and meaning of the communication's designer.
Another link to the State Express 555 cigarette company (albeit questionable) is where the designer of the Leo communication places the word Train - in the same section of dates as FLT Three of a Kind (see here). Obviously, Express and Train can be linked through the railways, but here is an extract from Wikipedia: "The idea for the State Express brand came from the U.S.in 1893. Sir Albert Levy, a London tobacco merchant, was visiting the United States. While in New York State, Levy was a passenger on the Empire State Express train, which allegedly broke land speed records as locomotive No.999, the “Queen of Speed” sped its way from New York City to Buffalo".
One of the most prominent features on this communication is the pseudonym Zodiac, placed beginning on the date of the 20th. The next confirmed communication from the Zodiac Killer was the Melvin Belli Letter mailed on December 20th 1969. The connection to Leona Roberts was speculated upon in the last article: "On December 20th 1969, the Zodiac Killer mailed the Melvin Belli Letter, mimicking the words written in lipstick (supposedly by William Heirens) on the apartment wall of murder victim Frances Brown. She was discovered shot and stabbed multiple times in her 3941 North Pine Grove apartment in Edgewater, Chicago. The date of Frances Brown's murder was December 10th - the exact date that Leona Roberts was abducted from 749 Tormey Ave in Rodeo".
All of the above are simple word association games involving numerical values, that may have no resemblance to the meaning of both the Day-by-day forecast for Cancer and Day-by-day forecast for Leo, but the possibility of a connection between the dates and words is a tangible one.