Posterior means it’s behind baby, closer to your body. Anterior is when it’s on the outside. Yes, it could mean you feel movement earlier but not always x
Yes I have posterior too. I had felt flutters from 16 weeks but now (18 weeks) not so much! But yes usually means you can feel things earlier
I had anterior placenta with my first and felt nothing till 23ish weeks. This time it's posterior and I've been feeling movement since about 14 weeks on and off
Posterior is normal, Just means behind baby