Here are some results of my updated satpy-scripts (not released yet), showing midnight (UTC) passes, Metop-B.

Using files of single day:

files used for METOP-B-20220406-DAY-2359_noext.jpg: (option -t 20220406)

20220406 235203
20220406 235503
20220406 235803

files used for METOP-B-20220407-DAY-0002-noext.jpg: (option -t 20220407)

20220407 000103
20220407 000403
20220407 000703

Using files of 2 days:

files used for METOP-B-20220406-DAY-2359_ext.jpg: (option -t 20220406)

(note: for 20220407 only files of 00:00-01:59 are potentially used.)

20220406 235203 (one more segment???)
20220406 235503
20220406 235803
20220407 000103
20220407 000403
20220407 000703

files used for METOP-B-20220407-DAY-2359_ext.jpg: (option -t 20220407)

(note: for 20220406 only files of 22:00-23:59 are potentially used.)

20220406 235503
20220406 235803
20220407 000103
20220407 000403
20220407 000703

Results of stacked files give comparable differences.

So the problem of around midnight passes seem to be solved here.

The other problem, the selection sunny/non-sunny ("use files between 00 and 04 hours (SORRY, NOT GOOD!)), is 'sort of' solved, but this has to be refined.

Cheers,

Rob.

Rob,

well spotted. Metop-B experiences a date change in daylight over Australia 20220407 00:00 as predicted here:

https://groups.io/g/MSG-1/message/32970

(bottom left image)

My script solves this problem automatically. The only issue is that for a given date 20220407DAY maximum elevation
is at 20220406 23:59. I should probably change in such rare cases the date on the image and in the filename
back to 20220406.  But maybe that is also confusing to the user who entered 20220407DAY?

Attached my latest solution. Beta testers welcome.

Cheers,
Ernst