That is not true. Simply declaring the connection handle will not store a value to it.
If you declare something like 'CYBLE_CONN_HANDLE_T connectionHandle' and want to use 'connectionHandle', then you need to assign the connection handle value at every connection under 'CYBLE_EVT_GATT_CONNECT_IND' event in Event Handler function of BLE.
connectionHandle = *(CYBLE_CONN_HANDLE_T *)eventParam;
Rather assigning the value in application and using it, you can use the stack variable 'cyBle_connHandle' directly as it is automatically updated by stack whenever a new connection is made.