When is Riots department responsible for lore going to make characters interact on a major scale?

When shoude we be expected to see Xerath vs Azir armys clash , the Darkin unite again , battle for Freljord (Ashe vs Sejuani vs Lissandra) , the Void attack and runeterra unite or something like that? And how longa are they going to build up the characters storys? Tnx