Tenant changes his mind about moving, already found new tenant

[Nicholas Jose]

Good afternoon, BP.

I'm currently creating systems on what to do if a tenant wants to break his/her lease and stumbled upon this link during my research: https://www.lsnjlaw.org/Housing/Landlord-Tenant/Leases/Pages/Ending-Leases.aspx. There's an ominous little sentence within the page and it reads as follows:

I know for a fact that NJ is a tenant-friendly state. So what happens if the tenant changed his/her mind about moving but I've already found a new tenant to occupy the old would-be-moving tenant's unit? Would having the tenant give his notice to vacate in writing be enough?