The SecPkgContext_Lifespan structure indicates life span of a security context. The QueryContextAttributes function uses this structure.
typedef struct _SecPkgContext_Lifespan {
      TimeStamp      tsStart;
      TimeStamp      tsExpiry;
} SecPkgContext_Lifespan, * PSecPkgContext_Lifespan;
 The security provider should always return these values in local time.