Daniel 12 like the rest of Daniel talks of the coming of Christ and the destruction of the 2nd temple - 1290 days = 42 months approximately = 3.5 years
and three and a half years is the duration of the First Jewish-Roman war which culminated in the destruction of the 2nd temple
If you connect this to Revelation 11:1-2 it is given over to the nations, and they will trample over the holy city for 42 months - John's description evokes the prior desecration by Antiochus
The number 7 has a symbolic meaning to the 2nd temple Jews - it is a combination of 3 (the number for God) and 4 (earth) - it is a sign of completeness. there is no gap between the 69th and 70th "weeks" -- note that the Apocalypse talks of the destruction in 69 AD when someone "shall cause sacrifice and offering to cease"
The 70 weeks bestowed six blessings that were bestowed as a result of the first advent - There is no doubt that Daniel's prophecy constitutes a prediction of Christ's advent 2000 years ago. For He appeard to the world at the end of "70 weeksp>An eternal righteousness also was proclaimed which overcame the mere righteouness of the Law; and the vision and the prophecy were fulfilled
In Hebrews 9:26 and 28 we read For Christ has appeared once for all at the end of the age to put away sin by the sacrifice of Himself.
As Jesus declares in Luke 4:16-21 Today this scripture has been fulfilled in your hearing
all the six benefits of the 70 weeks have been bestowed by Christ already. the last week ended in 69 AD -- and the common Jewish interpretation agreed with that - that Daniel's 70 weeks ended with the destruction of the temple in 69/70 AD
Though it’s a waste of time, I’ll just say,
Good luck with that!