Hey Ashamax,
Double check your emails, you should have one saying they are currently changing providers, so they aren't doing online tests until a later date. I re-applied and had an email to that effect and have actually just been sent an email today progressing me to the video interview.
"Online Assessments:
Please note, we are currently in the process of changing providers therefore you will not currently be able to access your online assessments. You will be asked to complete these at a later date should your application be progressed."