Probable issue if module runs for 50 days without being reset

[reivaxy]

The anti-sms-flood interval for each number that receives an alert stores the value returned by millis() when sending an SMS alert.
Next time sending alerts is checked, it compares the elapsed time between this value and the current millis() value.
But millis() resets every 50 days approximately. The stored value, before the reset, will then be bigger than any millis() returned value for the next 50 days => no more alerts sent.

[reivaxy]

Needs more investigation, a while ago I thought it would not be an issue (and wrote it down!)