Due to late changes in who the "Try Gutenberg" callout should be shown to (see #44680), it was decided to release 4.9.8 third release candidate yesterday, the originally scheduled date for final release.
The feedback from many in the community about that aspect of the callout has been very much appreciated!
The 4.9.8 final release will now begin:
Please continue to test the 4.9.8 third release candidate.