The church in Chelmsford is open to all believers in Christ.
According to the Bible, the church is God's heart's desire, and His means to fulfill His eternal purpose. It is the assembly, the Body of Christ, the new man, the bride of Christ, the warrior, and eventually the New Jerusalem.
There is one universal church across the whole earth and throughout all time since our Lord Jesus died and resurrected. All those who have received Christ by believing into Him are part of the church. According to the Bible, there should be no divisions in the church. Believers should not be separated by race, status, traditions, method of practice, or differences on minor theological points.
Since the church is the Body and bride of Christ, we should not take any other names. We should simply be the church. In the New Testament, the only designator of a church was the city in which the believers were. When the believers were in Rome, they were the church in Rome. When the believers were in Ephesus, they were the church in Ephesus. This was not their title, it was merely a description of what they were.
It is through the church that God will gain what He is after, to be expressed and glorified on earth. It is the church as the warrior which will defeat God's enemy. It is the church, particularly the overcomers, which will end this age and bring the Lord back, allowing Him to set up His kingdom on earth and usher in the New Jerusalem for eternity.