Snapper can be found pretty much everywhere at the moment, and as always the key is to work the tides.
This is particularly important when fishing the channels, and reports suggest snapper are turning up in all the channels. The Rangitoto Channel off A Buoy is holding snapper, and with strong currents it is a good idea to arrive at before low tide and fish through the slack water. This way both tides can be tested, as one usually produces better on the day and the first hour of the incoming is often the best time. You can start with small sinkers, increasing the weight as the current gets stronger.
Some people will use both a ledger rig and a trace below a sinker, and both will work but on some days one will outfish the other system so you can start with both and adjust accordingly. The general rule of thumb is - the stronger the current, the longer the trace. Conversely with little current baits can be moved by lifting the rod occasionally, and moving baits seem to work better than static ones.
But when the current is really pushing at mid-tide it can be hard keeping the gear on the bottom. There are several solutions - you can lift anchor and drift, or move out to wider areas away from the constricting confines of a narrow channel like in parts of the Motuihe, Tiri and Sargeant's Channels. Or try a heavy sinker with an extra long trace, or with a ledger rig simply thumb the reel while keeping it in free-spool so the gear moves slowly along the sea bed with the current. A fish will pick up a bait and swim away and when the line goes tight, start winding. There is too much line out to raise the rod and strike as the stretch in the line will absorb the energy. Winding will set the hook, and if recurved hooks are used the fish will hook themselves.
Tough baits are good in this situation, as you will not know when the bait has gone, and pilchards do come off easily. Fresh kahawai, jack mackerel or mullet are ideal, cut into small chunks for ledger rigs and strips for a running rig and trace. The white body of a squid with the skin scraped off, cut into strips, also works well.