AV vote campaign bypassing UNISON?

Alan Johnson MP, former General Secretary of CWU and until recently a senior member of the Labour Shadow Cabinet, has criticised the ‘depressing conservatism’ of trade unions on electoral reform:
http://www.bbc.co.uk/news/uk-politics-12706074

Although unions such as GMB and Unite have lined up to support the mainly Tory-led campaign for a ‘No’ vote (in support of the first-past-the-post status quo), it is unclear where Britain’s biggest union stands on the question which will be put in a 5 May referendum.

The FT claims that UNISON is ‘remaining neutral’. Can any UNISONActive readers clarify the position?
http://www.ft.com/cms/s/0/ade1952e-4a80-11e0-82ab-00144feab49a.html

Contact us at http://unisonactive.blogspot.com/p/contact-unisonactive.html