Civilization 6 - Relics - what happen when you run out of Relic slots?

There was this one time that I had an apostle with Martyr promotion - you get a relic when this apostle dies in combat. I lost him in theology combat and I had no appropriate slot for the relic. The end result that I can assure you is:

• You won't get any relic out of the event.
• You won't have the option to move your existing art to make room for the new relic, etc

In my case, the apostle died and the game notified me about losing a unit but there was no notification about wasting a relic opportunity whatsoever as far as I can remember. The game just proceeds as if that apostle has no promotion.

When I reloaded the game, made some room for the relic and put the apostle into his doom again, I got the relic.

This was quite some time ago and my scenario is about Martyr promotion rather than a bonus from city state but I believe the game would proceed the same way for both scenarios. I encourage you to test it out and share it to the community :)