A 28-year-old male from Delhi with a family history of hereditary persistence of fetal hemoglobin (HPFH) is found to have elevated HbF (18%) on hemoglobin electrophoresis during a routine health screening. Genetic analysis reveals a point mutation in the γ-globin gene promoter (−175 T→C) that disrupts a transcriptional silencer element. RNA-seq of reticulocytes shows increased γ-globin mRNA abundance relative to β-globin mRNA. The patient is asymptomatic with normal hemoglobin and hematocrit. What is the most appropriate immediate next step in management?