A computer-implemented method, according to one embodiment, includes: performing a first read of one or more pages in a first page region of a first block. In response to determining that the highest RBER experienced during the first read is not in a first predetermined range, a first calibration procedure is performed on the one or more pages. A second read of the one or more pages is performed. In response to determining that the highest RBER experienced during the second read is not in a second predetermined range, a second calibration procedure on the one or more pages is performed, and a third read of the one or more pages is performed. In response to determining that the highest RBER experienced during the third read is not in the second predetermined range, a reliability counter which corresponds to the first page region of the first block is incremented.