Upcasting
When upcasting a spell, you increase its Spell Point cost by 3 to get the heightened effect that would otherwise be achieved by spending a spell slot of one level higher. When increasing the cost by twice as many Spell Points, you get the effect of using a spell slot of two levels higher, and so on.
Unlimited Upcasting: With upcasting no longer being bound to available spell slots, you can now upcast as high as you like and can afford by increasing the Spell Point cost further and further. The Casting Limit described below is the only other hindrance.
Other Upcasting Intervals: Some spells have been changed to improve in intervals of other Spell Point amounts than 3, such as with every 2 or 4 additional Spell Points spent. For those spells, the heightened effect thus is achieved by additionally spending the given amount of Spell Points.
Upcasting Cantrips: Instead of scaling with your level, cantrips that previously scaled like this can now be upcast. Unless the cantrip was otherwise changed (see in the Spells chapter), its first upgrade can be used by upcasting the cantrip by 3 Spell Points, the second upgrade by upcasting by 6 Spell Points, and the third upgrade by upcasting by 9 Spell Points.
Unlimited Cantrip Upcasting: When the rules of a Cantrip Upgrade describe a steady increase of effect that could be repeated infinitely, you can upcast it by 3 Spell Points each to improve its effect by another step. For example, the damage of a Fire Bolt increases by 1d10 with each Cantrip Upgrade, so you can now increase its damage by 1d10 for each 3 Spell Points you upcast it by, potentially increasing its damage far beyond what was previously possible.