There is perhaps no more vocal proponent of Full Preterism/Covenant Eschatology than Don K. Preston. Don & his former debate opponent Michael Bugg did agree on at least one major point: that, despite Christ's work on the Cross, the Law of Moses was/is binding on Jews up until Christ’s Parousia (Return) per their shared misunderstanding of Mat 5:17-20.
This error drove Michael Bugg from a regular Baptist to a Messianic Jew because, unlike Preston, he still awaits the Second Coming.
But Preston's approach, (Covenant Eschatology, "Full" Preterism), fares little better. By insisting that the Law of Moses remained in effect upon Jews after the Cross Preston sides with those who believed that faith in the Cross of Jesus was not enough for them to have a right relationship with God (righteousness), that the Jews also had to keep the Law of Moses - right up until the coming of Jesus.
A later debate opponent, Terry W. Benton, demonstrates how that error takes the guts right out of the Gospel that the Apostles preached. Archived at: “Debate On the Passing of the Law” http://www.eschatology.org/index.php?option=com_content&task=view&id=541&Itemid=92 and here, /?q=node/207 In this written debate Don Preston rejects the immediate efficacy of Jesus' Cross to retire the Law of Moses. To Don, something more than the Cross needed to be done to retire the Law of Moses. Here are Preston's own words,
"Let me begin by saying I appreciate Terry’s first negative. He expressed himself well, without rancor. This is appreciated. Unfortunately, his position is false, ... If the Mosaic Law was taken away at the Cross, as Terry affirms, ..." http://www.eschatology.org/index.php?option=com_content&task=view&id=545&Itemid=61
Don was responding to Terry Benton's statement that recapped the proposed debate:
"Proposition: Resolved: Obligation to keep the Law ended with the destruction of Jerusalem in A.D. 70.
Don K. Preston so affirms, and I, Terry W. Benton, deny.
This is the proposition that Don resolved to prove. My role in the negative is to examine whether he offered such evidence that positively affirms and proves the above proposition. By this proposition Don says that "I mean by this (To Keep) to obey and perform the commandments, precepts, and statutes". So, this means that Don is affirming that all of the law, including Sabbaths, circumcision, and sacrifices, and the obligations to and by the Levitical priesthood were an obligation upon Paul and all other Jews until AD 70." http://www.eschatology.org/index.php?option=com_content&task=view&id=542&Itemid=61
Christ is the end of the Law of Moses for righteousness for everyone who believes, Jew and Gentile alike, Romans 10:3-4: /?q=node/87 and /?q=node/207 After the Cross, obedience to the Law of Moses became merely a matter of "unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the Law [of Moses], as under the Law [of Moses], that I might gain them that are under the Law [of Moses]" (1 Cor 9:20). It was also remained a matter of submission to the civil authorities then in power in the land Israel, Romans 13:1-10. Insofar as salvation & righteousness before God, however, "Christ is the end of the Law of Moses for righteousness for everyone who believes," Jew and Gentile alike, Romans 10:3-4