Is there a queue implemented to execute one BLE commend at a time?

[MayaBloodsAI]

Hi (-:

I wonder is there a queue that make sure that only 1 commend execute at a time or should I take care of it in my development?
If for example I call:
subscribeToCharacteristic

then without waiting call to write command then will cause the notification to raise, should I count on the fact that the notification will be finished before the write commend (due to a command queue )