My travel plans are still fluid.

Meaning

The plans are not yet fixed and could change.

Examples

• John: So, have you booked your flights yet?
• Alice: Not yet. My travel plans are still <b>fluid</b>.
• John: When do you need to decide by?
• Alice: I'm hoping to have something more concrete next week, but my travel plans are still <b>fluid</b> for now.