An update from me.
DS1 been on Singular for 1.5 months and there has been no incidence of asthma at all!!! He has been riding his bike in the wind and cold - no coughing, nothing

It was originally prescribed by my GP. We saw the specialist last week and he is getting us the free 3 month trial. I dont know what the criteria is, but we qualify.
But even if I had to pay the full price to get it, I totally would!