For a time the only Auckland-based MPs at Parliament had been National leader Judith Collins and Act's David Seymour, and more recently National's finance spokesman Andrew Bayly.
The absence of those other MPs has meant their colleagues have had to fill in for them when speaking on portfolio issues and on legislation, as well as running question lines against the Government.
Several other MPs had made the move down before Mallard's announcement for the coming sitting week, and carried out their five-day isolation already.
Parliament's remaining Covid measures wil not change.
The restrictions of 60 MPs in the Debating Chamber meant they could not all go into Parliament for Question Time, and most other significant meetings - including caucus and select committees - were still held online.
Mask-wearing in the chamber and corridors will continue.
MPs will not be required to return to Wellington - the proxy voting rules that enable MPs to do their jobs without returning to Parliament will remain for now.
Labour chief whip Kieran McAnulty said some MPs who had remained in Auckland under lockdown would be returning this week, while some ministers would remain as an on the ground presence through the outbreak.
Exact numbers would be confirmed tomorrow, he said, but about 10 MPs were expected to remain in Auckland.
McAnulty said they had procedures in place to manage MPs in Parliament based on limit numbers.
National's chief whip Matt Doocey said National would not be bringing all of its level 3 MPs back to Parliament - next week seven out of the 12 MPs based in level 3 areas would return while five would remain at home.
He expected National to continue on restricted numbers for the rest of the year but the MPs who were brought to Parliament each week would be rotated to ensure all had a chance to spend time at Parliament.
Overall, 14 of National's 33 MPs are usually based in level 3 areas but Judith Collins and Andrew Bayly had already returned to Parliament.
Doocey said there were a number of reasons to leave at least some MPs in their electorates at such a time.
"MPs have commitments in level 3 areas with constituents. So we are taking a pragmatic approach."
Nine of Act's MPs will be in Wellington from Monday, with the one remaining MP Toni Severin returning from Christchurch on Tuesday evening.
Auckland-based MPs Karen Chour, Damien Smith and Simon Court had all returned last week and completed part of the five-day isolation before the rule change.
Severin has now received her first dose of the Pfizer vaccine, after seeking expert advice over a medical condition. All nine other MPs are now fully vaccinated.
A party spokeswoman said they would sub in MPs in and out based on who was needed to keep in line with number limits.
A Green Party spokeswoman said aside from co-leader Marama Davidson, who returned to Wellington last week, the three other MPs based in Tāmaki Makaurau - Chlöe Swarbrick, Ricardo Menéndez March, and Golriz Ghahraman - would all remain there.
They would do their Parliamentary work from there, including select committees and caucus meetings over Zoom.
The four other MPs and Davidson would alternate sitting in the House at any given time in the same way they have been for the last few weeks, she said.
Co-leader James Shaw is currently in Glasgow, Scotland, in his capacity as Climate Change Minister for the COP26 climate change conference.
The party was also pushing for a hybrid/video/in-person Parliament in the short term, which was being looked into.
Both Te Pāti Māori MPs Debbie Ngarewa-Packer and Rawiri Waititi are based outside level 3 areas and so have not been affected by the rule changes.
Mallard also confirmed he had asked Parliamentary Service to investigate making available rapid antigen testing to attempt to "keep staff safe".
The Speaker has previously signalled a vaccinations certificate is likely to be introduced for Parliament in the future.