The rules state:
When a player passes, they must discard cards down to their Card Limit if necessary.
also:
Only when a player passes will they have to discard down to their Card Limit, which is determined by their Politics score.
Take the following scenario: Black is at their card limit. During an Action Phase, Black passes. Later that same Action Phase another player completes a Shipping Track which awards a Governor card to Black. Black now has too many cards.
When does Black discard? Immediately, at end of turn, or not until they pass in the next Action Phase?
The above rule quotes pretty clearly indicate that Black would not need to discard until they pass in the next Action Phase. But, what if there isn't another Action Phase? For example, what if the phase in question is the last Action Phase of the game? Does this mean a player could score more cards than their card limit allows?
However, the following quote seems to imply that the card limit is lifted only during the Action Phase (because it's not mentioned anywhere else):
When drawing cards during the Action Phase there is no restriction on how many cards a player may hold...
This could indicate that the card limit is enforced continuously after a player passes (because they are no longer able to draw cards), but it's not worded very well because what about the rest of the Action Phase when not drawing cards?