Small Manufacturer FBM to FBA

I’m a small business owner and manufacture one small size, relatively low cost product. I wholesale this product for a long time already through my own channels, but also got on Amazon to bring this product direct to consumer.
I’m toying with the idea of moving from FBM to FBA to see if it will help increase our sales volume. For people who have done this before, what did you notice? I’d appreciate your input.
How long was the process from FBM to FBA?
Are the higher fees worth it?
Did your sales go up? How much approximately, percentage wise?
Did you keep your FBM listing as well?
How much stock do you keep at the warehouse?
Do you think I could still get there before the holidays?
Any other recommendations? Tips?
Thank you!