Additional theme options disappeared?

Maybe a month ago or so, my colleague and I discovered a setting in Zoom that allowed us to customize the appearance of the app. There were a number of background images to choose from, and I selected a delightful vector-style illustration with leaves and such. Today I noticed my app is back to "normal" and the only customization options I can find are just the three different colours (Bloom, Agave, Rose) and Classic. 

Was I hallucinating about those additional customizations? Is this something that perhaps the IT administrators at my company have turned off? Or is there some other explanation?