Since you are claiming that your arrival at this conclusion is mathematical, show your work, please.
Here is what I assume you've done:
1054 AD - 1000 year reign = 54 AD.
If this is not the methodology you used, please show the steps you used in your arrival.
Also, there should be no "pretty much on target." It either is or it isn't.
1) I must admit that I first got the number 54AD from the preface to onr of my Bibles, which claimed that Matthew was written around 54AD.
It did not say this figure was cointraversial, and I never thought much about it.
It hardly seemed relavent at the time.
But when I read the passage rev 20:4 in the Theistic Evolution Bible it made sense that this was the actual case.
In debates like these, with you, on these threads, people did raise agruments similar to your own behavior.
For a while, I dismissed such quibbling as unimportant.
It seems very reasonable that this was the 1000 years of what historically can not be denied as one apostalic church.
So the 19 year difference from 35AD (crucifixion) thru 1054AD was too close to a 1000 years to take your type of criticism too seriously.
Even with that figure, 35AD, the 1000 years is so close as to be satisfactory in my opinion.
2) But then I read that Jesus said he had to go so the Holy Comforter could be sent.
Now that really intrigued me.
Since we know that Matthew says people need stay alert, and when they see the end coming, 70AD, be ready to flee, this Book of Matthew HAD to be between 35AD and BEFORE 70AD
(Why "warn" people when its already too late???).
The whole issue then is a matter of 35 years, 17.5 years being the mid-point in any of the two extremes.
To write The Book Matthew immediately after the crucifixion seems unreasonable.
So does assuming Matthew would have warned people to flee Jerusalem the same year or within a couple of years of the great destruction and impending diaspora.
So for argument sake, 35 AD + 17.5 year = 52.4AD.
3) Then I researched all the "Expert" opinions and arguments, eliminating those of 70AD and afterwards.
These are the ones I used:
Date and place of composition
Ancient ecclesiastical writers are at variance as to the date of the composition of the First Gospel.
Eusebius (in his Chronicle), Theophylact, and Euthymius Zigabenus are of opinion that the Gospel of Matthew was written eight years, and Nicephorus Callistus fifteen years, after Christ's Ascension--i.e. about A.D. 38-45.
According to Eusebius, Matthew wrote his Gospel in Hebrew when he left Palestine. Now, following a certain tradition (admittedly not too reliable), the Apostles separated twelve years after the Ascension, hence the Gospel would have been written about the year 40-42,…
Today, Catholic critics, in general, favour the years 40-45, although some (e.g. Patrizi) go back to 36-39 or (e.g. Aberle) to 37. Belser assigns 41-42; Conély, 40-50; Schafer, 50-51; Hug, Reuschl, Schanz, and Rose, 60-67
Protestant and Liberalistic critics also are greatly at variance as regards the time of the composition of the First Gospel.
Zahn sets the date about 61-66, and Godet about 60-66; Keim, Meyer, Holtzmann (in his earlier writings), Beyschlag, and Maclean, before 70, Bartiet about 68-69; W. Allen and Plummer, about 65-75;
When averaged out , these educated guesses equal 55.41AD as the date for the Book of Matthew.
http://www.earlychristianwritings.com/matthew.html
4) Since no one REALLY knows, de facto all these opposing arguments, I say God was right and accept 54AD making the prophecy Dead On correct.