Block explorer is little bit buggy, as we found out during POS issue. Don't rely on it completely.
Wait for block explorer to be upgrade to new version as well.

It is based on the reward system with diff, once it reaches over certain value, 50 VC is payout.
Another custom algo is added now, even if it is 50, reward drops further 10% every 7500 blocks.

It is designed to reward early miners, just like bitcoin. But with lot of other variables that bitcoin never offered.
If diff falls too low, so will the reward. At the end more miners mining higher the reward & vice versa.