The last Blood Moon Tetrad was September 28, 2015. Exactly 726 days later is the Revelation 12 GREAT SIGN of September 23, 2017. Not only is it 726 days later but the GREAT SIGN day of September 23rd contained exactly 726 minutes of daylight. This is the only day of the year to contain 726 daylight minutes !
The blood moon Tetrads were filled with pointers to 726 , which is Strong's Greek word Harpazo meaning rapture. Strong's word numbers are alphabetic Bible vocabulary , so they are Biblical in every sense. See the link for much more !
Forty months from the GREAT SIGN of Revelation 12 is January 23, 2021.