What if my 180 days does not line up with a tax year? When do I submit the 180 days out of SA?

If I work for more than 183 days outside SA, but my 12 consecutive months does not line up with a specific tax year. Say the last month fall in the next tax year, does it then mean that I will get tax back that I have paid the previous tax year for the days outside SA?

The 12 months is in a calendar year (Jan to Dec) not tax year (Mar to Feb) so that will be fine.