I received back to back notification for earning Steward badges for the same reasons:
You can see there are total 13 Steward badges have been awarded in last one hour multiple times for same review type:
Is there any bug with Steward badge?
This is not a bug; it's part of an update to the review queues. You now get one Steward badge for every 1,000 reviews in a single queue. For more details, see Steward badge can now be awarded multiple times -- backfill details on Meta Stack Exchange.