GTM WideIP Persistence

I am trying to disable wideIP persistence from a few locations, but am having difficulty finding the method. I assumed the persist none command would be the solution, but on this rule on GTM (9.2.4 HF1):

when DNS_REQUEST {
  if { [IP::addr [IP::client_addr]/24 equals "10.10.192.0"] \
    or [IP::addr [IP::client_addr]/24 equals "10.20.192.0"] } {
      persist none
  }
}

I get this error:

 

01070151:3: Rule [nopersist] error:

 

line 4: [undefined procedure: persist] [persist none]

 

I thought maybe the TTL command would work, but setting TTL 0 actually sets the DNS record TTL to 0 that is returned to the client, which is not what I want.

If anyone can help with determining which commands are available on GTM, and if persistence can be disabled on GTM, I'd appreciate it.

Support case number is C358989