Hortus has informed that the Wow PTR 2.3.2 has been taken down and it marks the end of its phase.  Everything points to patch 2.4 heading to the PTR servers quietly soon.

Hortus: We are taking down the PTR realms early to do extended hardware maintenance today. They will not be returning. This will conclude the 2.3.2 PTR phase. Thank you all for participating in the 2.3.2 PTR, we hope to see you all again in future phases.