Interesting. Findings of the trial being presented to parliament today
https://news.sky.com/story/major-breakthrough-most-firms-say-theyll-stick-with-a-four-day-working-week-after-successful-trial-12816198
I read that Starmer has offered Sunak his support.
Edit - something about it here
https://www.google.com/amp/s/www.politico.eu/article/labour-keir-starmer-vow-uk-prime-minister-rishi-sunak-brexit-deal/amp/