Barker v Westbridge International Ltd, EAT on 8th June 2000 (not reported)
Full text judgment is available free on the EAT web-site.

(i) for the purposes of deciding whether a person is suffering from a disability within the meaning of Disability Discrimination Act 1995 s.1 the relevant date is the date on which employment actually ended not the date on which notice of dismissal was given.

(ii) the employer's knowledge or lack of knowledge that an employee is disabled is irrelevant for the purpose of deciding whether he has been discriminated against by reason of disabiity with the result that a tribunal can use the benefit of hindsight to decide whether, at the date of termination, it was likely that the adverse effect of the impairment would last for at least 12 months from the date of injury with the result that it could be considered "long term".