Those things should not be the same, as you pointed out. Nodoka is hinted to have a connection to the world itself, and Noriko is led by Nao-chan. Tsuneyo is hinted to have a connection to Wires, the girls that remember (everything) all have a connection to the roof.
One other point of interest is that this cycle isn't randomly happening, it was engineered to be this way by foreign entities. Akira remembering, Maya giving in, Ayane surviving, Nao-chan being sent as help, Spring arriving - all of this is part of a larger plan (or to be more accurate multiple plans to make this cycle different). So definitely it isn't all just because the cycle is taking longer, since the reason it's taking longer isn't random.
Edit: I should probably give a concrete example. So, Noriko's school sinks in, that brings her to Akira's school, which leads to her giving him a box with Niki's letters - that's the moment he remembers his first memory of being the real Akira. Fast-forward a few hours, he ends the night on a roof with Maya, Noodles and Himawari. This was not a random event that just happened. Another example: Himawari shows up to sell Akira the very same scarf that Maya had when Akira accepted her feelings, she breaks down when receiving it, which kickstarts her giving in process. There are many such cases of things being nudged in a specific way.