Can't make the panel send something that isn't configurable. CID event codes are automatic based on the ZT in the M1. The M1 doesn't support 229 zones (208 max including KP). Unless your M1 has some major issues that aren't showing in the log, there's something else going on. The M1 logs the dialer test (which auto resets and doesn't randomize too greatly upon it's reset, unlike other panels).
A dialer test is relatively straightforward and would be difficult to prove otherwise. Easiest way to prove this is not your issue is to disconnect your M1 from the phone lines for a 24 hour period. While it may be possible a non-standard phone line or service could cause data transmission issues, I think there's something else going on.
To put it out there, there are only a handful of panels out there that support that many zones and have the ability to send a service request report, either automatically or via a keypad sequence:
Ademco/Honeywell: V-250 (can't generate a service request)
Napco: Firewolf 255 or X255 (can't generate service request)
Bosch/Radionics: G series, 9412 or larger (Been a while since certified, but don't remember them being able to send a request for service)
ITI/GE/UTC: NX8 (does not generate request for service; not possible)
2GIG: No panel capable of that many zones
DMP: Capable of sending keypad report requesting service, have multiple panels that encompass that zone number.
FACP's vary significantly if they have a native dialer (not possible to send anything that doesn't exist as a normal CID code) or "bolt on". If it was a fire dialer, it may be possible it is referring to a maintenance, clean me or dirty chamber on a specific detector (Z229) but this also goes hand in hand with the size and type of the panel that it's supporting at least 250 devices, as the majority of manufacturers classify a module different than a detector for counts.