Try thinking of the IT systems as that is what is causing the problem.
The grass was growing (and waiting) at the training ground so could have been laid any time.
The grass was laid when it was convenient - it could have been laid earlier but there was no rush, and a small delay in bringing it to the stadium allowed other (non essential) work to be done to complete the stadium more.
The grass couldn't have been laid earlier. The installation was put back due extra work needed inside the bowl. They had to lay boarding over the sanded trays to allow the cherry pickers to manoeuvre over. Once the work was complete the boarding was removed and the grass installation started