Will laying on stomach allow seroma to lower back move to front?

If the seroma cavity is communicating with the front of your scar, then laying on your stomach will bring the fluid forward with gravity.  If the seroma pocket is walled off posteriorly, then no.

Thank you for your question. Your PS most likely wants you to have compression on the area to push out fluid. Speak to your surgeon to have a complete understanding of your care plan. Best,

We don't know if position is as important as compression to support healing, and adequate drainage of course. Stick with your surgeons suggestions and seromas evntually will resolve.

Swelling after liposuction can last for several months.  Depending on the modality used final results are typically not seen until 6-12 months postop.  Compression can help reduce swelling after surgery, and is used commonly after abdominoplasty and liposuction cases. Continue to be patient with your recovery.  Make sure you discuss in detail  and understand your plastic surgeons postop instructions at each postop appointment.