After drawing his Zanpakuto, Ailin's instruction of Toshiro Hitsugaya was no longer limited to teaching Toshiro how to control his spiritual pressure. He had now begun introducing Toshiro to Zanjutsu and Shunpo as well.
As for Hakuda and Kido...
Well, given Toshiro Hitsugaya's current height, training in Hakuda would be the least efficient option. It would be nothing but a waste of time and energy.
And as for Kido, before Toshiro could control his spiritual pressure as freely as he wished, it would only harm both others and himself.
Later on, aside from when Ailin and Toshiro practiced Zanjutsu or spiritual pressure control, they used Shunpo to travel.
As a result, even without Ailin leading the way, the two of them reached the Seireitei in just three months.
Of course, during that time, every night after Toshiro had fallen asleep, Ailin would return to the Kuchiki Clan estate. Then, before Toshiro woke the next morning, he would hurry back to Toshiro's side.
Otherwise, even though Ailin had already told Haruko Kuchiki about Toshiro, there was no guarantee that Haruko would not overthink things.
Toshiro could not be blamed for being stunned.
In fact, even Ailin, who frequently traveled between the Rukon District and the Seireitei, felt a sense of disconnection every time he returned to the Seireitei from the Rukon District.
The Seireitei stood at the very center of the Soul Society. It covered an area of 133,000 square Rei Ri, with a radius of roughly 365 Rei Ri.
Perhaps most people were unfamiliar with the concept of a "Rei Ri," but Karakura Town, where the protagonist Ichigo Kurosaki lived, did not even cover 0.5 square Rei Ri. That was enough to show just how vast the Seireitei truly was.
An ordinary Shinigami would need forty days to make