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Sixth bullet point on the image
Personally, I'm gutted. As an ironman, extended daily dungeoneering challenges are the only way to get comparable xp rates to a main account given that we can't do large floors or sinkholes and elite dungeons offer paltry dungeoneering xp. And shifting tombs was a joke from the beginning, so probably no need to go down that route again.
E: u/ItsLuckyDucky linked this from the comments of that tweet. Possibly means you'll be able to do any one of the three activities for the daily rather than being forced to do a specific one (which would be absolutely horrendous), but we'll see.