Personally I’m of the opinion it should be localized to whatever locale you are in if possible. So I look for New Moons locally and this can affect the date of holidays in the continental United States.
"on his knees three times a day, praying and giving thanks before his God"
- Daniel 6:10
Weekly, Monthly, and Yearly Celebrations
"Therefore, do not let any man judge you
in eating or in drinking,
or in part of a feast, New Moon, or Sabbath
(which are a shadow of the coming things),
but the body of Christ." - Colossians 2:16-17