Halo infinte armor kits dont let you use their individual peices

My question more than anything, is this a bug or a feature because if it’s a feature that is one of the most annoying and misleading things the developers could do to armor customization. On top of that theres no point to it why would you not let people use the peices of armour from the kit when they’ve already paid for the whole thing. I hope this is a bug because if it’s not I’m refunding my battle pass . All I want to do is remake my reach spartan but I cant because peices I need are locked to different kits.