Orange published a list of connection requirements some time ago. If you stick to them (various send options in defined format etc), the connections are very stable.
TLDR
https://lafibre.info/remplacer-livebox/durcissement-du-controle-de-loption-9011-et-de-la-conformite-protocolaire/
TLDR
https://lafibre.info/remplacer-livebox/durcissement-du-controle-de-loption-9011-et-de-la-conformite-protocolaire/