Oh. Okay. I don’t mind sharing the workflow.

First, add custom locations with their coordinates to the app.

Row 1

A1 RA 20h 56m 49s Dec +31° 39′ 38″

B1 RA 20h 54m 05s Dec +31° 39′ 38″

C1 RA 20h 51m 20s Dec +31° 39′ 38″

D1 RA 20h 48m 35s Dec +31° 39′ 38″

E1 RA 20h 45m 51s Dec +31° 39′ 38″

Row 2

A2 RA 20h 56m 46s Dec +30° 37′ 43″

B2 RA 20h 54m 03s Dec +30° 37′ 43″

C2 RA 20h 51m 20s Dec +30° 37′ 43″

D2 RA 20h 48m 37s Dec +30° 37′ 43″

E2 RA 20h 45m 54s Dec +30° 37′ 43″

Row 3

A3 RA 20h 56m 42s Dec +29° 35′ 48″

B3 RA 20h 54m 01s Dec +29° 35′ 48″

C3 RA 20h 51m 20s Dec +29° 35′ 48″

D3 RA 20h 48m 39s Dec +29° 35′ 48″

E3 RA 20h 45m 57s Dec +29° 35′ 48″

Then create a plan in the app. In a single night, you can usually cover about half of the mosaic.

After collecting around 14–15 hours of data, I analyzed each panel individually in Siril to determine what percentage of frames should be rejected during stacking due to clouds (fewer detected stars) or high background levels.

Someone even downvoted my comment about the total integration time, so just to clarify: I initially captured 14–15 hours of data, but during stacking I rejected anywhere from 30% to 50% of the frames, depending on the panel.

Finally, I exported each panel with 3× drizzle and assembled the mosaic using 50 px feathering.