Just as God effectively brought all Israel against Yeshua and the gospel (for the Gentiles sake and their salvation), so is He bringing all nations against Jerusalem/Israel (towards the salvation of His chosen nation). God is altogether righteous and true, and will glorify His holy name through His judgments.
The Blood Moons, solar eclipses, increase in wars, earthquakes, economic instability, are all signs which Jesus spoke about. God is definitely using these signs to draw attention to something — and to Himself. For the believer, they are harbingers of the times we live in. But also for the believer, we need to be careful not to ‘divine’ by these signs.
God does things when not expected, so we cannot say — Shemitah or otherwise — that such-and-such will happen at such-and-such a [specific] time. We can not make everything ‘fit’ legalistically precisely what we try to logically figure out what God is going to do. The Holy Spirit leads us into all truth; and the Lord Messiah said that He has told us beforehand what is going to be so that, after it has happened, we will know that He told us so!