Unplanned visits and SDTM rule SD1060

Hi,

We use a constant number (e.g. 99) for all unscheduled visits. The problem is when a subject has two unscheduled visits, those will be listed as separate rows in SV and check SD1060 (Duplicate VISITNUM) fires. Due to my understanding of SDTM it is allowed to have several unscheduled visits listed in SV for one subject.

CDISC SDTM IG 3.3, 4.4.5 Clinical Encounters and Visits
The easiest method of populating VISITNUM for unplanned visits is to assign the same value (e.g., 99) to all unplanned visits, but this method provides no differentiation between the unplanned visits and does not provide chronological sorting.

Can this check be updated regarding unscheduled visits?

Example:

SUBJID  VISIT          VISITNUM  SVSTDTC
1003    Screening       1        2021-01-24
1003    Unscheduled    99        2021-02
1003    Randomization   2        2021-02-01
1003    Visit 1         3        2021-02-15
1003    Unscheduled    99        2021-02-17
1003    Visit 2         4        2021-03-02
1003    Unscheduled    99        2021-03-02
1003    Unscheduled    99        2021-03-04
1003    Visit 3         5        2021-03-15
1003    Unscheduled    99        2021-03-17
1003    Follow-up       6        2021-04-05