None of those dates matter tbh. The only date that'll matter is your eCoPR's date as that makes you a PR on that day (for citizenship related day count).
FD isn't even a real date that shows up on GCMS notes, iirc. Also, FD isn't even FD to begin with. Till someone gets their eCoPR, none of the intermediate stages imply anything permanent (e.g. post P2 application rejections have happened for non-accompanying spouse gamification applications).
So, focus on eCoPR's date, everything else's date is immaterial.