What has been your experience of flexible working?

Personally for some aspects I would say is being very positive. In fact my team is based in the US, and the best time for us to talk is early morning in my region. Being at the office by 7:30 or 8:00 in the morning can be very challenging in Tokyo, and therefore having flexibility is definitely good!
However I miss the human contact, seeing my team members face to face, having lunch with them, walking to the office.
I would say that the ideal situation should is an hybrid system.

Before the safety measures were tightened, I was working on the flexi-arrangement, 3 days working on site, and 2 days working from home. We are allowed to adapt the schedule based on what's on our work plan and weekly schedule, if we have early team meetings and late night calls, we are flexible to manage the work time to ensure we are productive in those meetings and our routine work engagement.