Can I file for eviction prior to tenant failing to vacate?

[Nat C.]

I just bought a duplex and gave the tenants a notice of 15 days notice to vacate.

They don't have a lease and have paid until the end of August.

They have already stated they are not leaving at the end of the month.

My question is, can I lodge the eviction application now, to get a court date booked in or do I have to wait until the end of the 15 day period and then apply?

I imagine the courts are backed up and I will be waiting some time for my hearing date.