There’s often an Allen wrench that comes with the garbage disposal. I keep it under the sink. When the thing jams, follow the directions in the manual, and I won’t need to come out. Another plumbing tip, don’t believe the myth about putting lemon peels in the disposal to make it smell better. That will just make it jam faster. These are the things you should never pour down the drain.
Plumbers in Australia have licensing requirements that differ from state to state but it is generally accepted a 4-year apprenticeship with a further minimum experience of 2 years (6 years total) and a further curricular requirement as a benchmark for licensing. Licensed plumbers are also expected to maintain minimum relevant training requirements to maintain their plumbing license