1 cm per day OR the diameter of the largest lymph node exceeds 5 cm during the 5 day wash out. 2. For subjects with lymphocytosis, the increase in the ALC exceeds 2x109/L per day OR the ALC exceeds 100,000 x109/L during the 5-day wash out; b. Arm C: No minimum washout is required after discontinuation of ibrutinib (or other BTK inhibitors) c. Approved PI3 kinase inhibitors: Subjects may start study treatment within 3 days of discontinuation of approved PI3 kinase inhibitors.