Plot reads When revealed choose an opponent. That opponent cannot reveal a new plot card during the next plot phase

H ow exactly does this impact the next plot phase; does this effectively limit the opponent's only choice during step 1.2 to their "locked" plot and it is revealed again during step 1.3...

OR

...does that player skip those steps and the locked plot is considered already chosen and not revealed; so 'when revealed' abilities will not re-activate?

The plot is not revealed again.

Many thanks for quick response; if the plot isn't considered revealed again, there's some interesting interactions with plots that have 'until you reveal a new plot' text especially Double Dealing - where you could potentially gain the text of two different plots or the same plot twice (e.g. reacting twice to winning dominance by copying the text on A Feast For Crows twice) although using 'when revealed' abilities remain unusable with this plot - unlikely but interesting.

Such a great game!

Ruling clarified for the Art of Seduction below for reference -

The opponent's active plot during the next round's plot phase is considered already chosen, cannot be changed at this time and is not revealed again; 'when revealed' abilities will not re-activate and choices made when the plot was initially revealed cannot be altered.

However, The Art of Seduction does not stop a plot being changed outside any phase except the next plot phase - an opponent may still reveal a new plot outside the next round's plot phase if able e.g. if " The Rains of Castamere " agenda is triggered or if At Prince Doreen's Behest was revealed - It is the active plot during the next plot phase that is the one that remains in place regardless of when it becomes the active plot.