The category to which a Reservist belongs depends on their duties and their level of commitment to a particular Service.
Standard Volunteer Reservists
Although Volunteer Reservists train over many years for active duty, they are only mobilised when absolutely necessary. In most circumstances, the Ministry of Defence (MOD) uses ‘Intelligent Selection’, which is the process of identifying willing and available individuals for specific appointments. This includes consulting with the Reservist's employer.
All Volunteer Reservists make a serious commitment to training. For the majority of them, this is around 30 days a year, made up of some midweek evenings, some weekends and one15-day continuous training period (Annual Camp).
Full-Time Reserve Service (FTRS) gives Reservists the opportunity to apply for a full-time post for a fixed period (this is different from mobilisation). Because of the valuable experience this provides some employers choose to grant sabbatical leave for such duties. However, you are under no legal obligation to reinstate an employee who resigns to carry out FTRS commitments.
Additional Duties Commitment
Additional Duties Commitment (ADC) gives Reservists the opportunity to undertake part-time work with the Armed Forces. This could be with a Regular or Reserve Unit, but it’s more likely to be within a headquarters establishment. ADCs sometimes form part of a job-sharing arrangement. The minimum commitment is 13 weeks - at least one day a week throughout this period.
You don’t have to give any employee additional time off to undertake ADC work. However, like FTRS appointments, employers may choose to do so because of the valuable experience such opportunities provide.
High Readiness Reserves
High Readiness Reservists (HRRs) have specific skills which the Armed Forces may occasionally need but at short notice. Reservists have to volunteer for High Readiness status, and if they have a full time job (or work more than two days a week) they will also need to have the written consent of their employer. This consent takes the form of an agreement that is renewed annually. If they are mobilised, an HRR can be asked to serve for up to nine months.
The Sponsored Reserve concept enables the Ministry of Defence to enter into a defence contract on condition that an agreed proportion of the contractor's workforce has a Reserve liability. These Reservists can be trained and called out to undertake the contracted task as members of the Armed Forces.