In his letter to the San Francisco Examiner on July 31st 1969, he addressed the envelope to S.F. Examiner. In his letter to Melvin Belli he addressed the envelope to Mr. Melvin M. Belli, using dots after abbreviations in the addressee. His letter to the Los Angeles Times again abbreviated the addressee to L.A. Times. The only exception from July 31st 1969 to January 29th 1974 was the envelope addressed to the Vallejo Times-Herald on July 31st 1969. It was addressed in full, using Vallejo Times Herold rather than V.T. Herald, or Vallejo Times (used in two of the July 31st letters). The envelope to the Vallejo Times-Herald (confirmed as Zodiac) was the only communication out of 15, from July 31st 1969 to January 29th 1974, that did not abbreviate the addressee and include full stops. In fact, the letter to the Vallejo Times Herald was the only time up to the Exorcist letter that Zodiac ever used the full name of the newspaper he was addressing.
This should give you extreme pause of thought when you consider the previously debunked October 28th 1987 Halloween letter (click link). This communication not only carried the full address of Vallejo Times Herald, just like the 1969 envelope, but both contained no full stops or commas, both carried the "Please Rush To Editor" phrase twice, both contained 13 words, both used "Calif" for "California" and both contained extremely excessive postage. The postal rate in 1969 was 6c, but the Zodiac placed 24c on his Vallejo Times-Herald envelope (an excess of 18c). The postal rate in 1987 was 22c, but the author affixed 44c worth of stamps (an excess of 22c). These were by far the most excessive postage used in any Zodiac or suspected Zodiac communications. When you consider the fact that a copycat would never have seen the 1969 Vallejo Times-Herald envelope in 1987, he did a remarkable job imitating the real killer in all of the above, not withstanding the fact that the handwriting looked eerily similar. The author would have had handwriting available to him from published Zodiac letters and the Dripping Pen card envelope published in the November 16th 1970 San Francisco Chronicle, but how on earth does he use this to mimic the July 31st 1969 envelope so perfectly in 1987. The author of the 1987 envelope could have designed it in a multitude of different ways, yet he just happened to choose the exact wording from an envelope in 1969 to which he had no knowledge of. The October 28th 1987 envelope (shown below) is the best available image we have currently.
It is also my belief that the July 31st 1969 envelope, October 28th 1987 envelope and September 25th 1990 Celebrity Cypher postcard were all addressed misspelling the word "Herald" to "Herold". The July 31st 1969 and September 25th 1990 communications most certainly were. If I am able to secure a clearer image of the October 28th 1987 envelope and it reads "Herold", then we can almost certainly link the Zodiac Killer to three communications spanning four decades.
1986 AND 1987 LETTERS - ONE HAND