Are ability modifier benefits to things like HP and trained skills retroactive?

Question

In Pathfinder 2e, a character's Constitution bonus affects HP total. A character's Intelligence bonus grants training in additional skills and languages.

Are these benefits retroactive?

Examples:

• If a character's Constitution modifier increases from +2 to +3 as the result of an ability boost, does HP increase by 1 per character level? So a level 5 character going from +2 to +3 Con mod would gain 5 hit points for the ability score increase?
• If a character's Intelligence modifier increases from +1 to +2 as the result of an ability boost, does that character gain another trained skill and learned language?

Answer 1

They are retroactive

Page 31 of the Core Rulebook tells us that:

If an ability boost increases your character’s Constitution modifier, recalculate their maximum Hit Points using their new Constitution modifier (typically this adds 1 Hit Point per level). If an ability boost increases your character’s Intelligence modifier, they become trained in an additional skill and language.