Subscribed Calendars not showing in availability

I was wondering if this is a bug or intended:
I currently have 2 caldav server i am accessing, one from home and another from a client of mine I frequently work for. I have admin access to both Nextcloud instances. To show my availability to my client, I wanted to share my personal calendar on my personal caldav server via subscription to my clients caldav server. I can see all the entries from my private caldav server on my clients server on the Website and on all devices connected to the server. The availability of the entries are also showing as “unavailable” on my clients server. But If the client checks my availability by inviting me to an event, they can not see any entries which come from a subscription. Is that normal behaviour? Can it be changed?