Armstrong, after resigning suddenly in September 2016, returned in March and went on to assist with the team at the 2017 Confederations Cup campaign.
Hudson is being assisted in Wellington by New Zealand Under-20 coach Darren Bazeley and goalkeeping coach Paul Gothard.
"That's over to the gaffer and he picks and chooses his staff," said All Whites defender Tommy Smith today, when asked about the absence of Taylor. "That's not something we concern ourselves too much with. We are just concentrating as players on being in the best shape possible for the match."
The All Whites completed another closed training session yesterday afternoon, as they continue their buildup to Saturday's big clash.
"There's no two ways about it - we've got more than enough to cause them problems," Smith said, "but we want to keep those cards close to our chest."
Smith said the All Whites' chances had been boosted by having Burnley striker Chris Wood and skipper Winston Reid.
"It's great to have a full-strength squad, which we haven't had for a long time. We're quietly confident that we can go and cause an upset," he said.
Although it has been some time since he played alongside Reid, Smith says there've been no problems with the West Ham defender slotting sweetly into the back four.
"A player as good as Winston is always going to slide straight back in - we know how good he is and how strong he is for us."
Additional reporting - NZN