Trailing interjection? "So, I'll just take that, then" Is the "then" now? Should it be "than" because I'm taking it rather than you?

This question Are constructions like "That's me out, then" primarily British rather than American? is more about "that’s"

This question’s answers When a person replies with a sentence starting with "then"/"than", should it be then or than? are very close, but the "then" is almost a conjunction there, not an offhand interjection

Related, the "yes", "right", "no", "ja", and "okay" in

• The one around the corner, yes?
• And we’ll meet again on Tuesday, right?
• We don’t want to be too hasty, no?
• We’ve covered this topic before, ja?
• So we will only stay a little while, okay?

do not read like classic question-tags as they do not use a form of "to be". They might confirmatory or leading

This is not in the form of a question, but it feels the same to me

• We’ll see you at the party, then

Even when the sentence has a question mark, sometimes it’s not really asking (allofunctional implicature); I just want to know what that last word is called and if it should ever be "than"

Cheers