I think the loophole for an overage player is this one ..
27.3.2 A Player (Player Y) has been registered with the New Zealand based A-League Club as a professional Player named in their A-League squad (including as a short-term injury replacement) or received an International Transfer Clearance (ITC) request to register with another professional football team (excluding as a short- term injury replacement). In such circumstances, Player Y must be replaced prior to 12:00pm on the Friday before the final round of the NL, unless Player Y’s referred registration/ or ITC takes place after the league, in which case Player Y may be replaced at any time provided such Player satisfies eligibility requirements set out under these Regulations.
Where Player Y is a goalkeeper, they may only be replaced by a goalkeeper and where Player Y is an outfield player, they may only be replaced by an outfield player. No Participant may replace Player Y with a Player from another Participant who has qualified for the Championship Phase.
... have Coastal Spirit lost anyone because they signed as a professional somewhere ? Suburbs used the equivalent in the womens league last year to sign a WCR player.