I think you are talking about the Terraform Registry community providers beta rather than the Terraform CLI v0.13.0 beta. Is that right?
If so, the community providers beta is a separate process than Terraform v0.13.0 beta which is being run by the Terraform Registry team at HashiCorp. I believe they’ve halted new beta applications for the moment because they have enough participants for the first round of feedback. The beta may reopen again in the future if they need some additional feedback, but that’s not being driven by the Terraform Core team (which is the team I work on) and so I can’t say for certain when or if that will happen. There’ll be guidance on the Terraform Registry site as the situation changes, though.