I generally find watching in release order tends to work better than chronological order at least the first time thru. The episodes are written assuming you aware of future events depicted in previous shows, if you aren’t they tend to lose a lot of their impact.
Congrats for getting thru TAS, I have tried and I just can’t.
I get that Ukraine won’t consider the possibility of ceding any territory, nor should they. They probably don’t like their allies even mentioning it.
But, there’s the separate issue of not being able to join NATO with ongoing territorial disputes. Without much context to go on, I would almost interpret this as something more along the lines of “Ukraine could join NATO tomorrow if the dispute went away (by whatever method)”.