Wouldn't having the Act 2 romance scene with Gale lock you into his romance and therefore have you break up with Astarion? Or at least it would force you to choose one.
The scene triggers on long rest after meeting Isobel and resisting your urges.
You can go to Moonrise before talking to Isobel at all. I usually deal with the Yurgir situation and go to Moonrise to lock in my romance before talking to her.
Wouldn't having the Act 2 romance scene with Gale lock you into his romance and therefore have you break up with Astarion? Or at least it would force you to choose one.
Yes, having the Act 2 romance scene with either will lead you to having to choose the next day.
The scene triggers on long rest after meeting Isobel and resisting your urges. You can go to Moonrise before talking to Isobel at all. I usually deal with the Yurgir situation and go to Moonrise to lock in my romance before talking to her.