Paul was told by God not to go to Jerusalem and he spent two years in jail for disobeying God. (Acts 22:18-23)
The point is, there is no reason for any saved Jew to be following Jewish customs.
The Holy Spirit told Paul through Agabus what would happen when he went to Jerusalem. Prior to this other Christians on his journey were also made aware by the Spirit what would happen. THEY urged Paul not to go. That is not the same as God telling Paul not to go.
I've always assumed that Paul was closer to the Lord's intent than these others. This MUST BE because Paul says to Agrippa, "21 That is why the Jews seized me in the temple courts and tried to kill me. 22 But I have had God's help to this very day, and so I stand here and testify to small and great alike."
He also says to those aboard ship on the way to Rome: 23 Last night an angel of the God whose I am and whom I serve stood beside me 24 and said, 'Do not be afraid, Paul. You MUST stand trial before Caesar;
There is no religious reason for a saved Jewish person to be keeping the old covenant rituals. They are free to observe certain customs for social reasons, e.g., the eating of certain foods, but those customs have no religious significance under the new covenant for either Jews or gentiles.
They also need to be careful to appreciate that certain customs cannot be kept in the fashion of the old covenant in any appropriate form, e.g., the sacrifice of animals for the "remission" of sin. This poits out one obvious difficulty with trying to observe the old covenant feats days. They were all intimately tied to the temple sacrifices, and once the temple was destroyed and the sacrifices ended, the feast could not be properly conducted. The Jewish feast customs today (Passover, etc) are based on post-exile rabbinic traditions. Jewish believers should be very wary about following such traditions and customs.