This shouldn't surprise anyone. The old covenant was still in effect until Jerusalem and the temple were destroyed. Do you imagine that one moment the old covenant ended, the new covenant was established and everyone knew exactly what to do?
The book of Acts records this history of the church beginning and new doctrine and practices that followed.
Do you have a quote that states the New Covenant started at the destruction of Jerusalem 40 years after the Cross instead of at the Cross when Jesus said it did.
he Ten Commandments in the ark of the covenant
Col 2:14 Blotting out the handwriting of ordinances that was against us, which was contrary to us, and took it out of the way,
nailing it to his cross;
The New Covenant was ratified at the Cross by the blood of Jesus.
Mat 26:28 For this is My blood of the new covenant, which is shed for many for the remission of sins.
At His death, It Is Finished, nothing could be added or changed to God’s covenant
John 19: 30 So when Jesus had received the sour wine, He said, “
It is finished!” And bowing His head, He gave up His spirit.
When Jesus rose He said He has all Authority over heaven and earth Mat 28:18-20. He already said not a jot or titttle can pass from His law until all is fufilled and that is when He comes on the clouds.
But if you have scripture that says the New Covenant started 40 years after His death, I am all ears.