>but creating a new system doesn't affect the old one in the slightest.
The idea of "new doesn't affect old" is an idea based on logical and temporal consistency. God is not bound to those.
In fact the current system of odd/even - as well as any other system and law, including the "excluded middle" - can be understood to be God's arbitrary creation. You consider it logically necessary and absolute just because God willed it so, you'd be considering a different one with any arbitrary change as just as logically necessary and absolute if/when God willed it :)
People create a lesser conception of God, with specific boundaries and limitations, and then gloat how he is limited. Well, let's instead start with the more common conception of God as limitless and with total arbitrary power.