In Malachi 3:6, God mentioned that “He does not change” with respect to the criteria of “not” destroying (“no” complete earthly annihilation implying also neither a complete annihilation otherwise):
“Because I, Yahweh, have not changed, you descendants of Jacob have not been destroyed.” (Malachi 3:6)
So, in Principle, the Act of Saving the World is “not” destroying anything permanently too meaning that He cannot change from being the “Saviour of the World”.
“We have seen and testify that the Father has sent the Son to be the Savior of the world.” (1 John 4:14)
In other words, “God’s Will” will come to pass regardless beyond the limitations of time-space etc.
Since He has “Willed To Save the World” (John 3:17, 1 John 4:14), “Willed To Save all men” (1 Timothy 4:10, 1 Timothy 2:4) and even “Reconcile All things to Himself” (Colossians 1:20), it shall surely come to pass eventually even beyond this temporal life:
“So will My word be which goes forth from My mouth; It will not return to Me empty, Without accomplishing what I desire, And without succeeding in the matter for which I sent it.” (Isaiah 55:11)
Only He can change it by “Willing otherwise” and good thing is, “no” Scripture states that He has turned from intending to ‘Save the World’ etc. So, “His Will” stands.
“Blessed Saviour of the World”