From the schedules it appears the aircraft and crew will sort of be based at Florence, Ibiza Malaga and Palma de Mallorca for the weekend to operate these routes.
Interesting that AGP and FLR continue to the end of the summer timetable in October, it'll be interesting to see what happens for the winter timetable.
BA Source has a useful summary
http://thebasource.com/ba-cityflyer-...turday-series/
'All services will operate as inbound returns from the non-UK airports to the following schedules:
BA7016 Florence 1110 – Bristol 1225 Saturdays
BA7017 Bristol 1310 – Florence 1625 Saturdays
BA7024 Florence 1710 – Birmingham 1835 Saturdays
BA7025 Birmingham 1920 – Florence 2240 Saturdays
BA7018 Ibiza 1310 – Bristol 1440 Saturdays
BA7019 Bristol 1525 – Ibiza 1850 Saturdays
BA7026 Ibiza 1940 – Birmingham 2125 Saurdays
BA7027 Birmingham 2210 – Ibiza 0145+1 Saturdays.
BA7020 Malaga 1330 – Bristol 1515 Saturdays
BA7021 Bristol 1600 – Malaga 1940 Saturdays
BA7030 Malaga 2025 – Birmingham 2220 Saturdays
BA7031 Birmingham 2305 – Malaga 0255+1 Saturdays
BA7022 Palma 1415 – Bristol 1545 Saturdays
BA7023 Bristol 1630 – Palma 1955 Saturdays
BA7028 Palma 2040 – Birmingham 2215 Saturdays
BA7029 Birmingham 2300 – Palma 0230+1 Saturdays.'