We couldn't find Huawei Mate 10, but one of our Engineer use Huawei Honour 8, so we borrow his mobile phone to check out the problem:
First, we make sure the WiFi is OFF
We start to search for available BT dvices, Huawei Honour 8 is listed in the first search.
We put the mobile phone along side our iDAP-6, the Huawei Honour 8 has iDAP-6 listed as available device, and vice versa at the iDAP-6 screen.
Select Huawei Honor 8 and try to get them connected
Successfully connected
So our test is failed because we can't replicate the problem in our lab., we are not saying the Bluetooth is flawless or trying to falsify your experience, we just failed to repeat the instance and identify the cause of the problem at this stage.
To be frank, BT connection between mobile and iDAP-6 is not a very high priority item except HiByLink, but since HiByLink requires a connection established from the mobile phone, so we are more or less established a habbit to switch on the BT on iDAP-6 and complete the rest of the BT connection procedure from the Mobile. We'll keep an eye on the available device list on iDAP-6 from now on, hopefully we can run into the situation as you have described, then we can diagnosis the problem effectively from there on.