At what point can an employer dismiss on the grounds of capability an employee who is on long term absence due to illness?

To help minimise the risk of claims, an employer should generally only dismiss an employee in these circumstances once a capability procedure, including the minimum statutory dismissal and disciplinary procedures, has been fully followed. It's usually preferable to commence the capability procedure sooner rather than later. If the correct procedure is not followed, the employee may be able to bring disability discrimination (see below) and unfair dismissal claim(s) against the employer (if he/she has more than one year’s service).

We assume from the question that the employee may also suffer from a disability (as defined by the Disability Discrimination Act). An important step towards