What is the ruling if experts confirm hope of recovery but cannot specify a time frame?

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If the experts confirm that sight may return but cannot specify a duration, the Diyah or Retaliation is due immediately. This is because waiting indefinitely would lead to the nullification of the liability arising from the initial injury, and the default presumption concerning sight is that it will not return. If sight returns before the mandated compensation is fully exacted, the compensation must be returned, as it has become evident that it was not legally required. If sight returns after the compensation has been fully taken, the recovered amount must be returned because it was taken without a binding cause.