The contract is due to start transitioning out in 2023 and runs through to 2026 but can be extended. The paramedic qualification changes in 2021 and there may be some pressure to get bums on seats, sorry, ar5es hanging out the door, before that takes effect.
The previous supply is in the course of drying up, market forces are against them, sub-contractors are expensive, alternative jobs are on land or in interesting places with warmer water, ...
It may require some luck to keep this on the rails.