Don't be naive and think your employer doesn't know about the change in the award applicability. Every top end employer I worked for was a member of some chamber of commerce, industry lobby group etc. One of the services provided by these organisations was to advise their members of any change in the industrial landscape. In one instance they knew about a pay rise in the award 4 months before we pilots found out about it. All they could do was pay up, including back pay, when we asked for it. It didn't send them broke, and we weren't blacklisted. In a court of law, ignorance of a law or legislation is not considered a legitimate defence. If you want a level playing field for your company and your employees, be assertive and ask for your legal rights. If you can't do that, you're in the wrong profession.