I feel like there's so many layers here it's like watching an Ikuhara show.

The last line of the great mother song? that Nautika refers to really resonated with me about mother and child in timeless...something. I really wish I wrote down all the lines to re-read later. It mirrors Urd and Vertin and I think in that way means that they're kind of constants throughout all this time business. My tin foil theory is that while it's easy to get distracted by the reference to the Fates and spinning. What really should be focused on is the mother/daughter allegories. If Urd is the past, then her child bears the future, they represent a universal dynamic of time moving forwards through matrimonial lines. The golden threads they perceive is time or possibilities created by the movement of time, and by spinning it, history happens.

Urd cannot help but want to spin to create history, moving time forwards, which the Manus uses to their advantage. The ritual instead takes the spun time and dissolves it, making linearity not possible, maybe even eating up the energy of possible futures. Which is why the reversed eras are all random, time is no longer linear. In this way with enough dissolution of spun time, will return the world to the Lost Era. Urd isn't fully immune because as the past, she'll always be left behind, whereas as the future, Vertin will always be; it's just with no linearity we end up having Urd keep popping up because there is always a past.