see also:
 In some years people recognize the first moon (Exodus 12:2) a whole month later than many of us because they didn’t like the first moon occurring slightly before the dead-center of the equinox calculated at the US Naval Observatory.  Lunar Sabbathers have all sorts of different concepts as to determine weekly Shabaths based on the Moon's phases. Psalm 81:3 is even attacked by some, claiming it isn't referring to the new moon and full moon.
If we read Exodus 40, it's clear the first day of the first moon was not a day off from work.
 There’s so many ideas, it’s little wonder that Yahusha refers to all of us as sheep without a shepherd.  In the grand scheme, these shadows (moon phases) are not even the finish line (goal). 
The goal is love;  when we have love for one another, all will know we are Yahusha's talmidim. It's love, not disdain, that we must have for one another.  Yahusha is looking for good fruit just as He was when He looked at the fig tree (Mt. 21:19).

  As you know, there are those who follow what they call the dark moon, and others calculate from the “sighted” or “sliver” moon (and it’s not limited to just these either – for example, some think the full moon is the new moon).
The sliver of light that may be seen at sunset on a very new moon is the fully-built first day's light.  The dark moon is the zero-point, and as light builds during the first day, a “sliver” slowly appears on the right limb.  This light building on the Moon's limb is a time record for the whole Earth, and it has no bearing on what time of day it happens to be at a particular location.  Those who begin with the “sliver” did not begin at zero-light, so 15 days later the moon will be past "full."  Time is being measured, and anyone who uses a stopwatch knows not to begin at “one” but rather “zero.” 
  By the 15th day of a sliver-mooner’s count, their moon will be waning, missing the amount of light they began with.  Psalm 81:3 becomes a problem for most who use the Islamic method (sliver).  We are scattered, so we have trouble being together about this, as well as how to track the Yobel (year of Jubilee).  The land we have been exiled from is to have a rest every 7th year (only if we’re in it; the Torah doesn’t apply to being exiled), and the 50th year is a year of release (debts, captives, property).  Our Redeemer, Yahusha, will restore all things, but for now He is preparing those of us who hear and obey His Words, which teach us love.  The festivals are shadows of His redemption plan, which we only “observe”.  We are witnesses to His redemption, and if we acknowledge Him as Redeemer we are His redeemed, doing the “observing.”  The world is to see us “observing” and acknowledge that we are servants of Yahuah for doing so.  Our confusion over when to observe the annual festivals is primarily due to our dispersion across the world (exiled long ago into the nations).  Even what we believe about time is certainly very wrong, but sheep we are – we just have to learn to love each other as our thoughts swirl around within us.  It’s all part of the test.  Even having all knowledge, and failing to love, is missing the point of it all. You and I will remain confused, and all who may teach us as well, until we set our hearts on learning to love, and using Yahusha’s Word to heal hearts, rather than as a hammer to crush hearts.
  The physical world is where we display our loving behavior, but it is a maze of incredible confusion. 
A day begins conventionally at midnight in the Pacific ocean, and New Zealand leads the rest of the world into what we call today’s “date.” It is doubtful the International Date Line will survive the Second Coming.
For those in Alaska and Hawaii, that same “day” will not even begin until 22 hours after it started in New Zealand
A single “day” will stagger across the Earth for 48 hours before it finally comes to a complete end.  Whatever location we may be on the planet will often cause incredible confusion for those in different locations marking the arrival of a new moon, whichever one we accept it to be (dark or sliver).  There are new winds of teaching popping up all the time, such as the “Enochian Calendar,”  Morning (sunrise) dayspringers, diverse kinds of “lunar” Sabbathers, those claiming an “agriculturally-corrected” calendar, and the “Creation calendar,” and now there are equinox-weekers resetting the weekdays by the equinox. There’s more I’m sure. 
  As we watch and wait for Yahusha to return, the “wise managers” who feed the household have to keep on a steady course amid storms blowing all around the household of belief.  The Yahudim, or “older brother”, has tracked the festivals and the weekly Shabath long enough to have it generally correct, although they miss the calculation to Shabuoth because they maintain Abib 16 to always be the “morrow after the Shabath”, and they count what are not actual weeks to reach the 50th day.
  To answer why I hold to the orthodox calculation generally, it is simply because the objective of Yahusha is to make the “two sticks” into one body, and the Yahudim know a great deal more than returning Afraim knows. 
The orthodox miss the “sign of Yunah,” causing their calculation of Shabuoth to float around in the real week. But, they know when a day begins and ends, when the weekly Shabath arrives, and when a new moon begins.  Amid all the confusion swirling around all of us, I advise the steady course set by those with thousands of years of experience navigating the days, weeks, moons, and years.
Perhaps it may be perceived as compromising, but those who received the Words of Yahuah hold first position, ahead of we who are being engrafted.
“What then is the advantage of the Yahudi, or what is the value of the circumcision?
Much in every way! Because firstly indeed, that they were entrusted with the Words of Alahim.” Romans 3:1, 2