I’m running H9Control 2.5.1 on an iPad 1 and iPad 4, pedal names were set to: P1, P2, P3, P4, P5. Immediately after setting them, H9Control would show the new names, but after power cycling the boxes and/or the iPad iOS Bluetooth menu shows the correct names: P1, P2, P3, P4, P5, but H9Control reverts back to the H9-SerialNumber form. I used H9Control->Pedal->General Settings->Device Name to set the name.
I also tried two other forms H9-01, H901. Both failed.
