It used to be a lot easier in the past; with full MVNOs the test window with the MNO could close and take weeks or months to access again, to name but one. However in the new cloud based world its all so flexible and easy that its easy to just keep slipping another month, but I have noticed that with this the number of failed MVNO, that is the ones that never make it to market, not those that launch and fail, is on the up.