FR965 simulator and real watch has different behavior with Bluetooth LE device

I have a ConnectIQ datafield that has been working in the field for several years, with many different watches.  Recently, this data field stopped working properly on a real FR965 running latest firmware.  The FR965 simulator does not show the issue.

The data field makes a connection to a commercial BLE device.  The issue is that this device is now rejecting a BLE connection update from the real FR965 after about 30 seconds.  This does not happen in the simulator.  This problem happens "under the hood" so I don't believe I have any control over how the data field manages the low level Bluetooth connection parameters.

I have provided details in  RE: FR965 BLE connection terminated because of unacceptable connection paramters 

I can provide Wireshark captures to show this issue on request from Garmin developers.

If there's a better place to report this, please advise!