A dual-mode BLE device identifies idle intervals within Bluetooth BR/EDR traffic communications. The identified idle intervals are used by the dual-mode BLE device to concurrently perform various BLE activities. For example, advertising packet transmissions, advertising packet scanning, connection setup, and/or data packet communication may be concurrently performed within identified idle intervals within the Bluetooth BR/EDR traffic communications. Packet transmission timing, advertising interval, scan window, and/or packet size are determined based on the identified idle intervals within the Bluetooth BR/EDR traffic communications. A scan window is adjusted based on timing of expected advertising transmissions and/or advertising interval(s) for saving power. BLE packets and Bluetooth BR/EDR packets may be detected in a single advertising channel. Maximal payload size is set based on the identified idle intervals within Bluetooth BR/EDR traffic communications. As a slave, the dual-mode BLE device updates connection parameters based on the identified idle intervals within Bluetooth BR/EDR traffic communications.