I think that we might be seeing batch 2 for some factions rather sooner than later due to endless spells. At first, when they previewed the box with a book I thought "that's it. maybe we will see more spells in a year". But then GW released 3 endless spells for Stormcasts and Nighthaunt. I think, that GW will push this new mechanic across most battletome factions and they will do it fast as long as they (endless spells) are still fresh and interesting. And if they release faction spells for Ironjawz and Sylvaneth I bet they will want to do it with a new battletome and new minis. So I think we might be seeing quite a lot, maybe not this year, but next year certainly.