I'm not sure how sustainable this 4day work week will be. Will it last the acquisition? Imagine buying a company that either makes your existing employee unhappy, make you lose the talent you just got, or forces you to convert the entire company into a 4 day week operation.
Two comments, you assume they intend to be acquired, and why optimize for something that late stage when you are trying to remain an competitive edge? (The edge in this case is a skillful happy workforce)