The creation of the Great Malvern-Brighton service (as Jim hints) came about as part of the December 2007 timetable re-shaping of "Cross-Bristol" services. You can find several related documents in the link below.
http://www.wellho.net/wccfoi/wccfgw3.pdfOne of the most interesting aspects of the 1043 Great Malvern-Brighton service is that it is one of the very few services out of the Gloucester-Westbury pattern that dont call at Stapleton Road & Lawrence Hill.
According to
FGW▸ , this is because the standard path into Bristol is flexed due to following a Westerleigh oil train. The
WTT▸ times for Parkway and Filton are in fact a few minutes later than in the
PTT▸ . The Temple Meads reversal is at the minimum already, due to the fixed path on the Coastway to Brighton, and so there is no time available to call at Stapleton Rd or Lawrence Hill.