Problem with CalDAV Transfer for URL Calendar Subscriptions

I added a new Calendar via “New subsricption from link (read only)”

This URL calendar will not get transfered via CalDAV.

This is annoying as on all of my devices I would have to read the Calendar URL.
On my Android Phone I even have to download ICSx5 additional to DAVx5 to have the calendar.

Can I make it so the calendar will get transfered via CalDAV?

You can’t, subscriptions are only exposed as cached calendars to the calendar web app.

Having ICSx⁵ to have the subscription on your phone (as exposed by DAVx⁵) allows you to have more control on the refreshment rate.

On my Ipad the Apple Calendar correctly imports the URL calendar.

How can that be?

It uses WebCal, not (really) CalDAV.

Apple Calendar & DAVx⁵ are the only clients I know of that are able to discover subscriptions collections and offer to subscribe to them.

I am using DAVx5 on my Android Phone and there does not seem to be an option to discover subscriptions.

The offical documentation also states (How can I subscribe to a HTTP (Webcal) or local .ics (iCalendar) file?):

Since DAVx⁵ 1.8, DAVx⁵ can detect CalDAV-advertised Webcal feeds and integrate them using ICSx⁵.

That’s what’s said in your quote : DAVx⁵ discovers the subscriptions (that’s the WebCal tab), but requires ICSx⁵ to actually subscribe to them. There has been talks of merging ICSx⁵ into DAVx⁵ IIRC.