I can't take credit for this but I'm going to outline how to fix voice navigation on your 1050 or 1040 at this moment. This is for phone navigation to your Bluetooth headphones.
Garmin isn't in a hurry to fix this so this is what you do step by step. This is the first time in months that my 1050 worked perfectly on long rides..
1. Delete Garmin Connect.
2. Go to site below and download apk 5.11.2. This is the last working version of connect that had working voice nav and time alerts.
connect.en.uptodown.com/.../versions
3. Plug your phone (android) into your PC and open the internal storage of your phone and drag in the older working 5.11.2 into phones folder. Then disconnect phone from PC.
4. Find a file browser on your phone and find the file you just dragged in 5.11.2. Agree to all the permissions and wait for connect 5.11.2 to install.
Once you verify you have this version, your old timed alerts and voice nav should work as normal... It's unbelievable Garmin couldn't have suggested this, seeing as how many of us are suffering with inconsistent voice nav and no timed heart rate alerts... it's a real shame we have to figure this stuff out ourselves. I guess if Garmin themselves were to suggest this they would be admitting to failure.. Pride is a terrible terrible thing...