I wanted to update to 0.12.5, however an apt-get update causes problems:
W: Failed to fetch http://apt.syncthing.net/dists/syncthing/release/binary-amd64/Packages Hash Sum mismatch
W: Failed to fetch http://apt.syncthing.net/dists/syncthing/release/binary-i386/Packages Bad header line [IP: 104.28.6.57 80]
E: Some index files failed to download. They have been ignored, or old ones used instead.
Possibly. The apt repo is (since just recently) behind cloudflare caching which may screw things up here. Give it a retry in an hour or so, otherwise I’ll have a look and maybe disable the caching.