Not all GPs working for CCAS were retirees returning to the NHS for the duration of the COVID-19 pandemic. We identified some GPs in this CCAS cohort as being active elsewhere in the NHS at the same time as they were working for CCAS. For example, 581 were already working in general practices and continued to work in their practices, delivering substituted or additional hours for CCAS. In these cases, it is possible that working hours were also reported in the General Practice Workforce statistics. 114 other GPs were also based in hospitals, such as within A&E departments, while 406 GPs working for CCAS can also be seen to have been working in other community-based settings such as walk-in centres, out-of-hours services or other specialist provision. Furthermore, with increasing trends of GPs adopting portfolio working, for example working some days in general practice and some in a hospital setting, it is possible that some GPs worked in more than one of these other bases as well as for the CCAS service.
GPs used the rostering system to register their availability to work sessions in four-hour increments. Not all GPs had the capacity to work large numbers of sessions, and in some cases, GPs were available to work numerous sessions, but demand meant they were not allocated these sessions. On average, the majority of GPs worked relatively few hours each quarter. For example, almost a third worked 40 or fewer hours for CCAS between late March 2020 and March 2021. Conversely, around a fifth of GPs worked 320 hours or more.