Particle already has a method of updating the OpenThread part of the DeviceOS. If you take a look at the notes in this DeviceOS update post from Feb 19, there is a quote:
- [Gen 3] OpenThread updated to 20190130 master with the fix for negative clock drift between HFCLK and LFCLK (#1684)
The OpenThread includes in the DeviceOS github are located here:
Are you concerned that Particle will not incorporate security fixes fast enough?