Problem accessing a synchronised magazine on a Device

My systems are running on linux (Leap 15.1), and devices are running various recent versions of Android. Nextcloud is version 16.0.3.

Synchronisation works well across my home network to several desktop machines, as well as to mobile phones and tablets. Calendars, contacts, documents, photos and files are all synced OK.

I recently setup a magazines folder on the desktop for my monthly Linux journal subscription, and automatically download a pdf version and an epub version to separate subfolders. Syncing works from desktop to mobile devices.

The problem is that each time I try to read one of the magazines on a device nextcloud tries to verify that the ‘file’ is the latest ! This makes it near impossible to open a magazine when I am away and not connected to the home network.

Is there any way to avoid nextcloud checking this each time I try to open a magazine?

Nextcloud is so convenient, I don’t want to revert to simply downloading a copy of each magazine to each of my devices, I much prefer nextcloud keeping the magazine folders in sync, but do not want it to keep checking that ‘file’ is the latest.

Appreciate any advice or suggestions to try.