Limited refresh rate for notify characteristics

Hi, I found a problem in curieBLE library with the subscribe at notify characteristics. My goal is to read with a 50Hz refresh rate the value of a characteristic updated at 50Hz through a BLE device. There are not problem in notify, but in subscribe, because through other bluetooth devices I can read easly the data at 50Hz. The maximum limit detected is 20Hz, the value is updated every 50ms constant! How can I solve the problem?
Thank you very much for your support.

Start by reproducing the reported behavior in the curieBLE library, comparing subscribe with notify characteristics and measuring the update interval. Trace the subscribe path to identify why values stop at 20 Hz despite the characteristic updating at 50 Hz. Done means reliably reading the characteristic at the requested 50 Hz.

Written by the indexing model from the issue text.