2323 gets hammered just as bad as port 23.
Not altogether unexpected, most would assume any evolution of 23 to be a suspect telnet port. Changing ports really only gets you a level of security through obscurity... something like fail2ban would be more effective longer term.
Spec
*** THE READER V4.50 [freeware]
--- SuperBBS v1.17-3 (Eval)
* Origin: There is no cloud, just someone elses computer! (21:3/101)