That's what her mini series was about late last year (Jean Grey #1-4). After being killed at the Gala, Jean goes to the White Hot Room and creates realities where she made different choices during key moments in her past. But she was also having trouble remembering her past.
And in Immortal X-Men #17, she was fragmented and reliving past events and randomly quoting herself from past issues (due to Mother Righteous bringing so many living mutants into the White Hot Room and interfering with Jean's reformulation and rebirth). Then Mother Righteous sacrifices spirit Jean in the White Hot Room to make a dominion and mortally wound the Phoenix and the White Hot Room.
In this preview Jean mentions having been in so many places but now her sparks are all together in one flame. That makes sense of the Jean Grey mini where a higher part of Jean's consciousness reconnected with the Phoenix and was observing her fragmented self dying in the White Hot Room. It was this part of Jean that gave some of her fire to Hope. The fire that Hope used to light the pyre in the previous issue.