Honestly would like if they add a new NPC in 6.4 that sells the old Series 1 items for Crystal Trophies. Then when 6.5 drops they add the Series 2 items and so on, so the old items get added around 1 year after being in the battlepass.

Old players get the reward early and can spend the trophies on new items, while new players or those that didn't get the reward back in the days have to decide on where to spend their trophies, new or old items.