Preparing work is work
One thing I needed to tell almost everybody on my team at one point or another is: Preparing work is work. What I mean by this is you should treat all the preparatory work, the daily reviews, the weekly planning and all other rituals you might have as work.
We ask people to work 40 hours per week – and that's plenty. I firmly believe people should completely disconnect over the weekend whenever possible. Properly resting and recharging will do more for your productivity and concentration than constantly being online, checking emails and messages on Saturdays and Sundays.
A lot of productivity articles have been written on the topics of weekly reviews and planning rituals – and doing them on Sundays. While I'm a firm believer in such rituals, I don't think you should sacrifice your Sunday morning or afternoon for them. The temptation to quickly check your emails, send that quick response or take a brief look at the newest pull requests is too big – and can easily become a huge time sink that keeps you busy for multiple hours.
The solution to this seems obvious in hindsight: do your rituals on Friday before leaving for the weekend, or on Mondays before starting your day. Doing these routines is important for your personal productivity, and hence, they should be important for your company. There should be no excuse necessary to do them in your regular 40 work hours. Preparing your work is work.