From a German site -

The 2017 sea ice minimum extent was reached on 2017-09-05. Sea ice extent is now increasing again.
https://seaice.uni-bremen.de/arctic-sea-ice-minima/

As a reference point, the USN plan from 2014.
USN Arctic Roadmap 2014-2030
http://greenfleet.dodlive.mil/files/...admap-2014.pdf

Scientific America weighing in on the above
The document said the Bering Strait was expected to see open conditions about 160 days a year by 2020, with the deep ocean routes of the Transpolar transit route forecast to be open for up to 45 days annually by 2025.
The document includes dozens of specific tasks and deadlines for Navy offices, including calling for better research on rising sea levels and the ability to predict sea ice thickness, assessment of satellite communications and surveillance needs, and evaluation of existing ports, airfields and hangars.
https://www.scientificamerican.com/a...tic-from-2025/

Hyperlink & summary.
Rear Adm. Stuart Munsch, Assistant Deputy Chief of Naval Operations, Operations, Plans and Strategy (N3/N5B), delivered the following remarks during the 7th Symposium on the Impacts of an Ice-diminishing Arctic on Naval and Maritime Operations at the Naval Heritage Center in Washington, D.C., July 18 [2017]