Meaning of "work ethics" in Australian English

While I have seen it on Aussie job sites, I don't believe that the use of this phrase is endemic to the Antipodes.

Flexible work ethic (normally used in the singular and rarely in the plural) is basically used to indicate that you should be ready to be a "team player" when it comes to working hours, sick leave, etc. If it's busy, you might have to work long hours. If somebody is sick, you might have to come in on your off-day to cover for them. If the office is short-handed, you might be expected to cope with additional duties beyond your assigned purview.

In other words, we are going to push you and you're required to budge.

While I agree that the use of ethic here is odd, I suspect that it is being used in the sense of principles rather than morality.

As an Australian English speaker, I can assure you that there is nothing mysteriously Australian in this usage. Any Australian should be able to recognise how dubious the phrase "flexible work ethics" sounds, just as you do as an American English speaker.

The author of the job ad is trying (but failing) to convey that the applicant should have a strong work ethic around the ability to be flexible in their working hours, roles, etc. The subtleties and ambiguity we picked up immediately in his sentence have gone straight over this guy's head.

We are simply looking at an example of the horribly mangled language that is rampant in job ads the world over. People are copying and pasting and plagiarising whatever sounds important and at the cutting edge of recruitment policy, without really understanding half of what they write into these ads.