In one of my playthroughs I have a F1/W1/Bard 9 (soon to be 10). I can learn wizard spells all the way up to level 5, because I have level 5 spell slots. I cannot at the moment learn level 6 spells, but when I level up one more time and pick bard (or any full spellcaster) then I will be able to scribe level 6 spells too.
