Complex sentence: In November 1851 a breakaway group formed a separate church which met at Roberts's residence, "Maesbury House", where their first pastor J. H. Barrow held a service on 21 January 1854.
Split into simpler sentences: In November 1851 a breakaway group formed a separate church which met at Roberts's residence, "Maesbury House". They were still meeting at Maesbury House when their first pastor J. H. Barrow held a service there on 21 January 1854.