In the Final Battle, do all spells have to be recast each round of combat?

Question

1. Investigators Refresh At the beginning of a round of combat with an Ancient One, the investigators may refresh their cards, use any character abilities, and adjust their skill sliders as though it were the Upkeep Phase. Next, the first player marker should be passed to the left. Finally, they may trade items among themselves as if they were in the same location (see “Trading Equipment” later in these rules).

Is this really an upkeep phase in every single respect, or is it a psuedo-upkeep phase with slightly different rules? Do spells have to recast every round? Dread Curse of Azathoth says it lasts until end of combat, and the rules specifically say investigators may refresh cards. If they chose not to refresh a spell would it mean that the spell would continue in effect, possibly for the whole battle without having to be recast at all?

EDIT: in addition, if investigators have blessings, do they need to roll to see if they discard them every round of combat?

Answer 1

From page 16 of the rulebook

A spell or weapon that gives you a bonus (even one that says it lasts until the end of combat) only continues to give you the bonus while you devote the required number of hands to it. You can choose to switch weapons/spells in later combat rounds, but as soon as you “release” a spell or weapon, it stops working for you. Similarly, spells that are refreshed (such as at the beginning of each combat round in the final battle) cease to work and must be re-cast.

And from page 6

Some cards exhaust themselves when used, which means that they are turned face down for the remainder of the turn. At the start of the Upkeep Phase, each player refreshes those cards by turning them face up. Simply remember that you can use face-up cards and that you cannot use face-down cards until you turn them face up again during the next Upkeep Phase.

So, exhausted spells are refreshed every round during the final battle and thus need to be recast. It's much simpler to think of the final battle as a combination of multiple combats through which damage carries over.