I've not been on here for a while, hi Fleecewife
I hope you are well.
I have a different angle on lights for poultry.
I keep my backyard hens in and under lights from end of October through to end of Feb (even when there is no legal need). The lights are on from 5am until 4pm (they still have some natural daylight and tend to go to bed before 4pm anyway). Jungle fowl originate somewhat closer to the equator, which has a more even daytime/night time distribution (longest night is 10 hours and its mostly around 8-9 hours) . If kept in Scotland in the winter without lights, they are not eating from 3.30-8.30 in the depths of winter and that is too long for my birds. I do get some eggs but I don't do it for that reason. I think I am doing ok, some of my original hens made it to 11/12 years of age. They have been domesticated a long time and some breeds are hardier than others but they are still basically jungle fowl.
Its quite easy to provide a good, indoor environment with lots of enrichment for hens-my place is very exposed and my hens do better inside in the winter, have now done it for 6 years. Ducks are a different matter!Much more difficult and I don't keep them in routinely.
I am in and out of different poultry units often for work, there may be issues but lack of food and water isn't one of them. Yes they want maximum egg production year round, but legalisation wouldn't allow them to not have food available as long as some backyard flocks do.
The five freedoms is a good basic level and care should absolutely not fall below that-more current thinking is more along the lines of 'a life worth living'. I am off to find the offending post!