The reason Flying Blue gave a minimum* of 12 months' notice is to give enough time for (interested) members to ensure they got to a "safe" position, in view of the new potential to lose as many as 299XPs during the changeover.

If they were going to implement the system as explained by the Flying Blue agent quoted in #394 (3 years added to the timer and a starting balance of 250XP; no loss of XPs at all) then they would not have had to give so much notice. There was no possibility of "losing" any XPs, so there was no real need to give such an amount of notice before implementing the change - intended to assist those affected with planning to get themselves into a better position.

(Also: the way the FB agent ran the algorithm in #384 is more generous; 3 years off the timer; start with 225XP; no XPs lost vs the actuality of: 2 years off the timer, start with 300XP, 225XPs lost)

I made a similar point in some other thread not too far back where someone was grumbling about having such little notice of the change - and which I unfortunately cannot find now, because I can't remember the ID of the poster that was grumbling, but it's someone whose year ends in October so they may read this and identify themselves/recognise the thread I'm talking about - the reason FB gave so much notice was so that people could "avoid" this horrible scenario of losing XPs. Ben Lipsey more or less confirmed that was the reason too.

*except for those whose year ends on 31 October; they had just under 1 years' full advance notice. Those whose year ends on 30 September will have had almost 2 years' advance notice of the change. Everyone else falls somewhere else on the scale between 12 & 23 months' advance warning