I find it very easy to upload the .fit files from my laptop that are available from my watch when I connect with the USB cable which I have been using anyway to upload to Garmin. I imagine Bluetooth should also work instead of USB. Almost as fast as automatic upload.
Never mind..... I see you are aware of it (Current discussion about ransom-ware attack at Garmin)
With my other watch (which appears to be dead) that would work, but this one connects only with an ANT+ stick, and that's just stalling out for now. No USB cable option with this one.