I'm a bit confused about how Table 1-1 (Ability Scores) and Table 1-12 relate to each other, as both include Max Spell Level entries.
Based one what I've read so far in this thread, I'm guessing that Table 1-12 tells us what the max spell level is that one can learn at a particular experience level (with the exception of Patron Spells, as noted above).
The score on Table 1-1 tells us what is the max level of spell that the PC can learn, period. That is, a wizard with an Intelligence of 9 may learn spells up to 2nd level only, and never any from above that level, even if it is, for example, a 3rd level patron spell. So, that wizard couldn't ever, under any circumstances, learn a 3rd level spell.
So, given that, a first level character, provided that he or she has both has the level of intelligence required (10 or above) and access to a 3rd level Patron Spell, can try to cast that 3rd level Patron Spell at experience level 1. Is this interpretation correct?