As you know, different doctors have different opinions. My AA/MDS expert recommended tapering after my counts had plateaued for 3 solid months. My local doctor wanted me to taper sooner because he has seen the harmful effects of cyclosporine on kidneys.
So, I ended up starting my taper when my platelets were over 100k for 3 solid months, even though they were still slowly trending up. I've been tapering for years now (literally) and am now down to 25 mg/day! Looking back at my platelet charting... about a month after dropping below the therapeutic dosage of cyclosporine (3 mg/kg/day), my platelets stopped their upward trend and have stagnated ever since. However, I am glad that I did the taper, even if my counts aren't perfect. Over time, despite tapering, the cyclosporine has caused me some mineral deficiencies and reduced kidney functionality.
52 yo female, dx 9/08, AA/hypo-MDS, subclinical PNH, ATG/CsA 12/08, partial response. Tried slow cyclosporine taper over 4+ years. Platelets fell, so back on cyclosporine. Trisomy 6 clone in 5% of cells.