When will older champion skills be "recoded"?

This isn't going to be one of those "Riot, don't forget to rework older champions" posts.

League has been a game for near 6 years now, and it's growth in popularity is absolutely amazing. The actual game itself has improved considerably (I still remember the graphics from Season 1). Coding has much improved, despite all the spaghetti code memes, with unique mechanics of champion kits (like Bard for example).

However, there are some older skills on older champions that need to be touched up in terms of coding. We all remember the days of pre-rework Darius where he could E you, and you would still get pulled back even if you escaped range before the animation finished casting (I still miss the old Skarner ultimate). This older coding made spells instant cast even if the cast animation was delayed.

Two champions (off the top of my head) still have this same problem; Annie and Cho'Gath . Each of their cone AoE abilities on W (Incinerate and Feral Scream) still have delayed cast animations, but have instant cast effects, unlike other AoE cones such as Cassiopeia's ultimate, Riven's Windslash, and Kassadin's Force Pulse. It's akin to being hit by an Ashe arrow or Caitlyn ult before the projectile even reaches us visually.

Will Riot find time to update these older champion skills, or will they just keep them as they are?