P: Cloud documents disappear after iPad has gone to sleep in mid-course of downloading

From my iPad Pro, I can't see a cloud document file that should be there. I can see the file on cloud from desktop version of Photoshop.

I posted this issue here, but nobody gave me an answer.

1.  I uploaded (save as, to the cloud) the files in Photoshop on my desktop PC.

2. I opened Photoshop on the iPad. The files were listed in "Cloud documents".

3. I opened the files. Pop up dialog said it should take long time as my internet connection was slow (in Japanese). Actually, my internet connection speed is about average, which is not too slow.

4.  My iPad went to sleep automatically.

5. I woke my iPad. I no longer could see the files. The download dialog was gone. Downloads didn't seem to be continuing. The files were not shown in the Cloud Documents. I still could see the files on cloud, from my desktop PC.

6. After waiting of one to 24 hours, the files re-appeared.

7. The files could be seen under "Cloud Documents" on https://assets.adobe.com/ when the files could not be seen in Photoshop on the iPad. From the web interface, the file could be seen even on my iPad.

Of course,  I used the same account for desktop, iPad and the web.
The issue above is reproducible. 

iPad OS 13.2.3
iPad Pro 12.9 3rd generation
Photoshop on the iPad 1.0.1
The file: 3.97GB, psb file created by Photoshop 2020, or the other file which is 480MB.