Cellular disconnect need/script for ppp in linux?

Using an xbee cat-1 cell modem in bypass mode with pppd (linux). There is information for appropriate net-chat scripts for connecting, but I haven’t noticed any for disconnecting? There are all kinds of warnings about making sure to disconnect from the cell network before powering down.

I’m curious if everyone is just on their own to write a disconnect script after pppd shuts off, or if something interesting happens during the lcp disconnect when pppd is terminated? As in, some sort of signal line does the cell disconnect for you and no ATSD is necessary?

You need to write your own disconnect function to safely power off the module before you can power it off.