I started at 35 weeks but u can start when ready. My friend waited and she had her baby early and becuz she didn't have her bag packed she was calling family to get this and get that from the home and stores. The last thing she expected was to go in early but she did and it happens. So it's ur choice u can always add as u go along.
Ftm also. I started packing around 33 weeks. 39 wks 2 days now. Honestly I'm still not completely done bc I keep taking things out, adding things, rearranging etc. Lol. I have the basics ready to go though