On windfarms of only two turbines, it is impossible to calculate Lost Production to Downtime in some cases.
For example, during a communication issue on one turbine, the other turbine works as reference turbine but the calculation is not performed in presence of any curtailment of the reference turbine.
Add a reference anemometer would allow the possibility to use either Learned or Default PC on the turbine which have no communication, using wind speed signal of the reference turbine.