The situation on the ground at Gatwick is better at the moment. Gatwick Ground Services (BA Ground Handling Subsidiary)have been pro-active in recruiting since last November/December in readiness for Summer 2022. Admittedly the BA long haul operation is far smaller than the LHR but it seems to be running smoothly.
I think companies of all types at Gatwick have been able to recruit fairly successfully as the surrounding area was badly affected by the impact of Covid on employment. Recent job fairs were also well attended.