@ Wara
These escorts are not 'Uber' and you can loose them. You say that you were at 50m, was this due to the depth of the area? Go deeper!
Also, you must now plan your approach, you can no longer just sit in front of a convoy at 0 kts and wait for it to pass over you. You will be detected.
The best approach is to come in from the side of a convoy, find a gap between the lead escort and the flanking escort. This way you will be in front of the flanking escorts sensor range and in the 'blind' spot behind the lead escort.
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