This usually becomes an issue when opposing trades are opened in under 2 minutes, and this happens at least twice.
There is no single default time standard that automatically makes this acceptable or unacceptable in every case. As a general guideline, having around 3 minutes between reversing trades is considered safe.
However, the review is based on the overall pattern, not only one exact cutoff. For example, if there are no flagged reversals within 3 minutes, but when looking at a 4- or 5-minute window the number of flagged cases increases significantly, such as from 0 to 6, then this also adds to the overall flag score.
In other words, the assessment looks at repeated short-interval reversals and the broader trading behavior, not just one fixed minute threshold.