When is the time of restoration?

Acts 1:6-9 “Therefore, when they had come together, they asked Him, saying, "Lord, will You at this time restore the kingdom to Israel?" And He said to them, "It is not for you to know times or seasons which the Father has put in His own authority. "But you shall receive power when the Holy Spirit has come upon you; and you shall be witnesses to Me in Jerusalem, and in all Judea and Samaria, and to the end of the earth." Now when He had spoken these things, while they watched, He was taken up, and a cloud received Him out of their sight.

Jesus tells them that they cannot know this, obviously, because it would be far in the future. He did admonish them for the immediate work they would be involved with.

Peter preached to Israel in Acts 3:19-21: “Repent therefore and be converted, that your sins may be blotted out, so that times of refreshing may come from the presence of the Lord, and that He may send Jesus Christ, who was preached to you before, whom heaven must receive until the times of restoration of all things, which God has spoken by the mouth of all His holy prophets since the world began.”

Christ has ascended and is waiting for a specific time to return, his return is not because all things have already been restored by or to the church. He returns in order to effect this restoration Himself. It is referring to the Millennium. It is “the presence of the Lord” which brings about the restoration- Christ does not return to earth as a result of the restoration, but to accomplish it. The Restoration is specifically promised to Israel on the condition of their repentance, Not to the Church. For he tells them to repent and be converted.
The genuine church, the spiritual body of Christ has already repented and is united in Christ. Acts 3:19 is about the kingdom of Christ upon earth with Jesus as the king physically ruling to bring things back into order.