How to ignore some versions for watch file?

[Roger Shimizu <rosh@debian.org>]

Dear mentors list,

I maintain a package that previously used vYYYYMMDD as version, but
now changed to v1.y.z
- https://tracker.debian.org/pkg/shadowsocks-v2ray-plugin
- https://github.com/shadowsocks/v2ray-plugin/tags

So my question is how to ignore the old version vYYYYMMDD, and only
detect v1.y.z as latest version for d/watch file?

BTW. I already read a few posts regarding on d/watch file [1][2], but
still didn't find a proper solution.

[1] https://wiki.debian.org/debian/watch
[2] http://eriberto.pro.br/blog/2013/10/07/how-to-write-a-good-debianwatch-easily/

Thank you!

Cheers.
-- 
Roger Shimizu, GMT +9 Tokyo
PGP/GPG: 4096R/6C6ACD6417B3ACB1