M.M.
After your first pregnancy, "lightning" doesn't typically occur until labor begins. So it's unlikely that she's dropped and you're not in labor.
So, she's probably just getting heavier, and gravity is pulling everything down now. You can stay dialated like that indefinitely.
I was a 3.5 for 3 weeks, and never went into labor on my own. We would up inducing.
So, sorry to bear the bad news mama, you've still got some "baking" to do!