Starting in late 2022, right when it began the deployment of the second regiment of Avangard missiles, Russia started an upgrade of missile positions. By late 2024, all positions of 368th missile regiment had been upgraded. All include a characteristic round above-ground structure that appears to be the guard quarters (Danwatch.dk found very detailed plans of the buildings).

What's interesting, the Avangard positions of the 621st regiment, which started receiving missiles in 2019 don't have buildings like that. There is a (round) guard house there too, but it appears to be smaller.

It appears that the deployment of Avangard has been completed. My understanding is that the deployment rate is two a year - it took three years (2019-2021) to complete the first regiment. In the three following years, 2022-2024, Russia probably completed the second regiment. The original plan apparently was to deploy 12 total. The FAS team also has 12 deployed Avangards.

(The position on the image and in the DanWatch story is at 51.097721 60.085756)