john smith
You have misunderstood the line. What I and OP DES wrote says it all but I will put it together for you. When engine fails after V1 the ECU detects a flame out and attempts a relight by energising dual auto ignition but since the aircraft is in flight phase 4 or 5 you only see on ECAM ENG START SEL...IGNITION. The full ECAM starting with THR LEVER..IDLE appears at 1500 feet(in phase 6) or 30 seconds after the failure ). These 30 seconds are not the ones we are talking about. After the ignition comes on the ECU does not time 30 seconds but monitors N2. If N2 drops below 40% the ignition is turned off. This is the end of auto relight. Now when ECAM appears and you select mode selector to IGN/START then you time 30 seconds. Here also ECU monitors the N2 and if N2 falls or remains below 47% N2 it attempts another auto start that is why you need to wait 30 seconds from then. When you select the ignition it termed as confirming auto relight.