@Dave52
Dave, a guest can only leave a review if they cancel on the scheduled day of the start of their stay.
They can leave a review even if they don't turn up, as long as the cancellation was on the day they were supposed to arrive.
If they cancel on the day before, they will not be offered the opportunity to leave a review, the system is automated and does not take into account special circumstances.
I have reviewed a number of guests who in fact did not get to arrive here, and they have reviewed me, but in each instance there was a special circumstance involved and the cancellation was on the scheduled day of the stay!
Cheers........Rob