Hawuei Doesnt know their own SLA for screen repairs

On Sunday, i took in my Hawuei Phone for a screen repair. They said it would take 7 days and i would receive an sms when the phone is checked in and when it is ready for collection. Today i received the FIRST email to say that they are awaiting parts. Yesterday Serge from the call centre said it would 7 to 14 days. Does anyone there know what is going on and what is the correct SLA? I need the phone urgently as i am using a friends phone and said it would only be for 7days. Disgusting service.