Level 6 & 7 mastery

From what I've heard the essence that we will get from disenchanting champions and skins in season 8 will be reduced. I assume the reason for that being is because we will get chests by leveling up, and we will get chests through the normal loot system that we are used to, or in other words more chests and shards? But does anyone know if the mastery levels 6 and 7 will be harder to unlock and if they will cost more? Could anyone with a PBE account possibly show any pictures of what is displayed on mastery tokens when you click on them so I can compare and calculate the difference to the current essence amount. (The reason I can't do it is because I don't have any leveled up champions on the PBE).