Very stressed about partner visa application

Hey,

So I'm a UK citizen, living in Australia with my partner on a WHV. I arrived late Feb, and have been living with my partner from the first day I arrived. We were in a relationship for a year prior to me coming to Australia doing long-distance, but have spent time together in-person before. When applying for my WHV I put that I was single, as I didn't think our relationship counted as it didn't meet the Govt requirements for a de facto relationship. I am now worried that when I apply for my partner visa they will question my previous visa relationship status.

I am super worried, we have plenty of evidence, but just don't meet the 12 month cohabitation requirement, and I have this discrepancy on my previous visa application.

My job and all me and my partners future plans rely on me being able to get a partner visa.

Can anyone please advise?