There is an old thread about this, which quotes the (then latest) rules to say that delayed reinforcements are placed before the HQs: https://boardgamegeek.com/thread/981151/reinforcement-phase
However, those quotes do not exist in the current version of the rules, and I can find nothing there to say that delayed reinforcements would be needed to be placed before the HQ.
Case in point: Turn 3 ANZAC arrives, and so arrives the British (delayed) fleet of Warspite, Indomitable and Hermes.
Is it nowadays legal to deploy those ships with the just arriving ANZAC?
The current rules say only (10.11)
Allied player places all reinforcements first, and then the Japanese
player does so
If the WIE level is 1 or greater, or if required by
Inter-Service Rivalry or an Event Card play, Allied player receives
all reinforcements from the Delayed Reinforcement box and all
Allied reinforcements for this turn are placed in the delay box.
In other cases, Allied player receives all reinforcements from the
Delayed Reinforcements box and all reinforcements for the turn to
HQ units and US B29 Air units can never be delayed.
No mention about needing to place delayed reinforcements first is in the sequence of play sheet either.
So, can ANZAC arrive together with the delayed British Fleet on turn 3? In Australia, for instance..