My understanding is that an electrician who is a Level 2 accredited service provider has qualifications exceeding those of a Level 1 electrician and that those additional qualifications relate to their training and ability to connect or disconnect network services – underground and above ground. In addition to having this training they would need to have been approved by the Distributor ( not retailer) as well as the NSW Dept of Industry.
The Level 2 electrician would therefore have the authority to remove & replace the main fuse.
Unsealing and resealing of meters would be authorised by the appropriate metering provider.