I just upgraded from the previous release and checked some APIs.
Could the warning at the bottom be somehow related to the upgrade?


$ bitcoin-cli -testnet getblockchaininfo | jq
{
  "chain": "test",
  "blocks": 1764143,
  "headers": 1764143,
  "bestblockhash": "00000000514399503aca1bffa0bc329646e54aaccdf439093c80b00b6fc87afb",
  "difficulty": 1,
  "mediantime": 1591701573,
  "verificationprogress": 1,
  "initialblockdownload": false,
  "chainwork": "00000000000000000000000000000000000000000000015bbaaea736421238f7",
  "size_on_disk": 27411014312,
  "pruned": false,
  "softforks": {
    "bip34": {
      "type": "buried",
      "active": true,
      "height": 21111
    },
    "bip66": {
      "type": "buried",
      "active": true,
      "height": 330776
    },
    "bip65": {
      "type": "buried",
      "active": true,
      "height": 581885
    },
    "csv": {
      "type": "buried",
      "active": true,
      "height": 770112
    },
    "segwit": {
      "type": "buried",
      "active": true,
      "height": 834624
    }
  },
  "warnings": "Warning: unknown new rules activated (versionbit 28)"
}