Have you given thought as to when Liko and Dot become an item in your canon
I have, actually!
New Horizons spoilers below.
So, their confession(s) actually come very early in the timeskip period. When the group circles around to ask Dot to join them in traveling again, Dot puts up a good deal of resistance. Liko, knowing Dot well, presses the issue, and says that she knows it's hard without Friede-
"You think I'm like this because of Friede!?" Dot snaps. "I'm like this because of YOU, Liko!" Her confession of grief turns into a confession of her love for Liko, which has been stagnant, but continued to fester for an entire year. It's hard to tell whether she even said so on purpose.
Liko returns her feelings. She says as much, with clarity. But, right now might not be the best time to make anything of it. Meowscarada is still rather jealous of her relationship with Liko, to say nothing of the emotional state everyone is in; they're just figuring out how to reform the Rising Volt Tacklers, or where anyone stands within it. All of the adults but Orla have declined returning. It's a turbulent time for the entire group, and a pretty bad spot to figure out a relationship.
In a rather mature fashion, they take a raincheck on their romance.
This pause lasts quite a while, and faces its first big turn around two thirds of the way through the story, if I had to put a pin in it!
Around this time, Liko tells Meowscarada she wants to talk about the situation with Dot soon. She's hesitant, but agrees to that... but before that can go anywhere, Spinel gets his grubby hands on Meowscarada.
She's kidnapped for his purposes. Liko's so broken up about it that she decides to be selfish and impulsive, and tearfully asks if Dot can spend the night with her.
The next morning, Liko admits she's slept in the same bed as her starter as long as she can remember. The thought of doing so alone was unbearable. Dot asks if she was just a replacement. Liko says she's not. She's loved her for a long time, too. Her absence on her streams... was because Liko couldn't bring herself to comment anymore. It was too painful a reminder of them being torn apart after Laqua.
They're in a strange place now, where they've done too much for either of them to take it back. They probably shouldn't have before consulting Meowscarada, but... Liko is human. She had a breaking point.
Liko and Dot are in a nebulous space for most of the last stretch, where they don't formalize anything, but they probably do rely on each other emotionally. This all comes to a head in the final battle, after Meowscarada regains her freedom. The circumstances of this allow her a peek into Liko's mind, and she sees what she's missed.
She can't find it in her to be mad at Liko; especially with what she's suffered. She 'threatens' Dot, saying that she better have taken good care of Liko in her absence. It's her way of accepting Dot into the fold while saving face for her usual jealous ways. From Spinel's defeat onward, Liko is formally dating both Meowscarada and Dot!
Other girlies make their way into the polycule later, like Ann and Hatterene; I assume these happen during Wonder Voyage! By this point, Meowscarada has matured, and she knows the depths of Liko's love for everybody. Her heart needn't be rationed; she has love to spare!
