Check out Redfinger's recent post about his jigging at Taupo in the thread below this - Freshwater Fishing Reports.
Apologies if you're fully up with the play, but just in relation to fishing near the river mouths, please make sure you don't breach the regulations which make it illegal to do anything but fly fish (not harling with a fly) within a certain distance of the river mouths. It used to be 300m, not sure what it is now.
Harling is always effective at this time of year, particularly in the pre-dawn and first part of the day along the shallows/drop off edge.
Casting spinning gear with a small ball sinker and a smelt fly is usually more effective than using metal spinners. I reckon small softbaits (NOT scented ones) would be worth a go, too. But again, all that has to be well away from the river mouth itself.