That’s an indication that they are on the stable release channel, as there are no newer Q builds currently, but please make sure … [HOWTO] Give complete /e/OS version info easily for support, answers, comparison etc.
The FP3 OTA upgrade from Q to R is for the stable release channel only.
First thing would be to backup every important data on the phones. Upgrades of the underlying Android version may work out fine more often than not, but it’s better to be safe than sorry.
If your friends are on stable, too, hitting the refresh icon in the updater a few times can make a difference in what gets offered.
You could also try to delete data and cache of the updater to reset it to some degree, then try again …
The “Updater” App has different names in different languages. If in doubt, switch your phone to English to find it.
The package name at the bottom of the App info page in the Settings is “org.lineageos.updater”.
Else … you could get the download URL for the stable R OTA file from https://ota.ecloud.global/api/v1/FP3/stable (see the “url:” lines there) and apply it via ADB sideload in recovery mode. At least users on the dev release channel have done this successfully keeping their Apps and data (including me), I don’t quickly find a forum reference to an ADB sideload upgrade on stable right now.
The procedure is layed out in more detail here … https://doc.e.foundation/devices/FP3/upgrade … but don’t use the R stable image downloads there currently, ADB can’t sideload these files, use the OTA file link from https://ota.ecloud.global/api/v1/FP3/stable.