The potential delegation of unclaimed VYB was explained in the initial white paper:

Until all 1,000,000 of the ‘claimable’ VYB have been claimed, portions may be delegated to members of the Verify Your Brain tribe, to compensate them for various tribe-related tasks.

Hive account@calumam is actively managing the VYB Curation Project as well as vyb.earn and vyb.contests.

Hive account@scholaris is actively managing the VYB Anti-Abuse Team, which includes serving as VYB's liaison with HiveWatchers and HDR.

Hive account@leprechaun is actively assisting with front-end management and enhancement efforts.

Hive account@eonwarped is, well, amazing in his assistance with front-end maintenance and development efforts.

In addition, the following has been initiated, as was also outlined in the initial white paper:

The first 50,000 POB received will be delegated to Hive account@scholaris.pob as ongoing compensation to support anti-plagiarism / anti-abuse efforts for Proof of Brain and Verify Your Brain. Scholaris.pob will further distribute the delegation as applicable to at least 4 additional accountholders for assistance in these efforts.