I'm still befuddled. A signed LOI is binding on both parties. Not sure where exploitation comes from.
As I noted, the pressure to get kids to sign before they're really ready.
I think an early signing period around this time of year would be fine. It gets kids signed who just want to enjoy their senior year without being bothered by tons of coaches. And the late period in Feb would be for those not quite ready to decide and the late bloomers who have big senior seasons.
But you'd still get the "kid, sign now because there might not be a spot for you later" pressure. Or the opposite, "don't sign with that school now, there might be a spot for you here later".
This happens in basketball but it's not that big of a deal since recruiting classes are small. But in football, this would happen a lot more.
I don't see that as a big deal. Having the signing period moved up helps kids concentrate on school in the fall instead of going on recruiting trips. Sure some kids would feel the pressure to sign, but they are already getting a ton of pressure to give their verbal commitment. Plus it protects kids who get hurt their senior season but already signed their LOI.