I've seen little evidence of capping in my circa 18 months as an...

I've seen little evidence of capping in my circa 18 months as an investor, until recently.
Usually it needs to be somebody with enough "ammo" to play the buy and sell simultaneously.

Somebody is trying to accumulate a larger position without paying up for them.
It's a game of win some, lose some, and orchestrated to bias to the win side over time.
The buys sitting at the 2.2-2.4c are likely the same crowd capping at the 2.5-2.6 level.

One large buyer could just as easily clean them out, but until that happens they retain control with a few million shares. Whilst there's no news flow that would offer a significant change in sentiment toward Aura, the game will continue. When news arrives it's game over and the SP will gap up.
They hope to have their fill prior to that news event.

Looking at the register it's likely a broker acting on behalf of a client. Nothing has happened to draw instos to the trough just yet, and we will know when that happens for sure.

If I had the cash I'd take out the 2.5 and 2.6 levels immediately. I'm fairly certain it will be a minimum 2x return before mid next year, but hey that's just me.