While Madison, Nan Tian, Helion and Jacob were dealing with the three gods, Shiro had her entire focus dedicated to creating a device that could resolve the energy build up problem.
She knew that the energy build up was a result of the source code changing rapidly so her solution was to use time magic once more and allow the energy to slowly disperse itself and stabilise the object.
The only problem with this was that she would need to create a new spell circle every time the energy fluctuated since her mastery over time magic was still lacking. If she was to make new spell circles constantly in quick succession, especially with something such as time magic, the drain would multiply with each spell. At the start it wouldn't be too bad but soon the drain will be too much even for her.