opkg update problems on Tessel 2

executing opkg update

C:\Users\soapdog
λ t2 root
INFO Looking for your Tessel...
INFO Connected to tesselfafi.
INFO Starting SSH Session on Tessel. Type "exit" at the prompt to end.


BusyBox v1.23.2 (2016-09-02 15:27:43 EDT) built-in shell (ash)

Tessel 2  /  Built on OpenWrt
root@tesselfafi:~# opkg update -v
opkg version 0.1.8
root@tesselfafi:~# opkg update
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/base/Packages.gz.
Updated list of available packages in /var/opkg-lists/chaos_calmer_base.
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/base/Packages.sig.
Signature check passed.
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/packages/Packages.gz.
Updated list of available packages in /var/opkg-lists/chaos_calmer_packages.
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/packages/Packages.sig.
Signature check passed.
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/tessel/Packages.gz.
Downloading http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/tessel/Packages.sig.
Signature check failed.
Remove wrong Signature file.
Collected errors:
 * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/tessel/Packages.gz, wget returned 8.
 * opkg_download: Failed to download http://downloads.openwrt.org/chaos_calmer/15.05-rc2/ramips/mt7620/packages/tessel/Packages.sig, wget returned 8.
root@tesselfafi:~#