T12, SP meant 'Working Holiday Visa' either subclass 417 or 462.
Difference is in the 'group' of states with reciprocal agreements and conditions/restrictions.
WRT to WHV and 'skilled job', Schedule 2 in Consolidated SOL (former regional employer sponsored migration stream) has pilots and instructors as skilled jobs.
So, work visa or permit, very similar stuff for joe public. Just like 'entry visa' vs legal status once in the country, as it may differ (e.g. USA).