In the interest of fairness, and to avoid conflict, I think it'd be a good idea to introduce 8-day weeks that both start and end with Sundays. 45 weeks of 8 days each would be 360 days. 9 months of 4 weeks each, and January to March only 3 weeks each, because I don't like those months. And the extra 5 or 6 days in a year can be Sundays too. But keep the 5-day work week!