Nylium doesnt spread when bone meal is used

Hello, I had a look into the upcoming 1.16 Nether Update release candidate snapshot and found that Nylium doesnt want to spread to other blocks when clicked with bonemeal. It only causes fungi and other nether plants to grow but the Nylium doesn't spread. Ive had a little search and I can't seem to find anyone having a similar issue. I have also set the random tick speed up to 1000 but no difference. the Nylium doesn't spread at all.