UPDATE 4.30pm UK: Halo developer 343 Industries has now said it is working on a way to replay campaign missions in the future - although there's no word on when that might be.
"We haven't announced a date but that is being worked on," 343 Industries associate creative director Paul Crocker told The Verge. "We want to have replay that works well, and when you have a more open game, it gets a lot trickier.
"We made a decision to improve the quality of the single-player campaign to ensure that, as a foundation, that it's as strong as it possibly could be so that we could then add the other features back in."
Here's hoping this arrives alongside campaign co-op, which is currently slated for May 2022 at the earliest.
ORIGINAL STORY 9.30am UK: Halo Infinite doesn't let you replay campaign missions, Microsoft has confirmed.
In a statement issued to Polygon, Microsoft said story missions are not replayable, breaking Halo game tradition established 20 years ago with Halo: Combat Evolved.
THERE MAY BE SPOILERS AHEAD.
"The postgame does give you the option to keep exploring the wider environment, but for missions like the first two, where you're not on the ring yet, you can't replay from the same save file," Microsoft clarified.
"You'd be able to get any remaining FOBs, targets, [and] audio logs, but the main story missions would not repeat."
I finished the Halo Infinite campaign for our recently-published review, and expected to be able to replay story missions at a different difficulty and with skull modifiers enabled, but this is impossible.
Instead, Halo Infinite spits Master Chief back out on the Halo ring, leaving you free to hoover up any incomplete objectives, such as Forward Operating Bases, and collectibles.
Halo Infinite is structured in such a way that main quest missions are siphoned off from the open-world action, often taking you inside Forerunner structures.
Objectives set outside on the open-world are, once complete, changed, and you're unable to give them another go within the same campaign run.
If you want to replay story missions, find missed collectibles from them or try them on a different difficulty, you need to start the campaign again from the beginning and work through the quests in order.
This is in stark contrast to previous Halo games, which let players jump straight into any completed campaign mission from the main menu.
The feature is an obvious casualty of Halo Infinite's shift to semi open-world, although perhaps a main mission replay menu is something 343 can add at some point down the line for those who managed to finish the fight.
As already announced, Halo Infinite also lacks other mainstay features, including campaign co-op and Forge mode.
As Eurogamer revealed last month, Halo Infinite campaign co-op won't be released until May 2022 at the earliest - half a year after the game launches. And Forge mode may not launch until late summer next year at the earliest.