[BUG] - `syncProgress` incorrectly says as `100.00` for Preview network (node 9.1.0)

External

Area cardano-node

Summary syncProgress incorrectly says as 100.00 for Preview network (node 9.1.0) when querying for tip even when it is not, see below response:

❯ cardano-cli query tip --testnet-magic 2 --socket-path ~/cardano-nets/preview/db/node.socket
{
    "block": 120020,
    "epoch": 29,
    "era": "Babbage",
    "hash": "a576fb4e48804bfb67f213a5dbc8554afa532b1b5f865e13e4ba364f095b5a7c",
    "slot": 2537607,
    "slotInEpoch": 32007,
    "slotsToEpochEnd": 54393,
    "syncProgress": "100.00"
}

At the time of writing this issue, preview is on block 2359827.

Steps to reproduce Steps to reproduce the behavior:

Spin up cardano-node v9.1.0 with provided configuration from fresh start.
Query for tip.
See that it immediately gives syncProgress as 100.00.

Expected behavior

syncProgress should indicate actual sync progress.

System info (please complete the following information):

OS Name: MacOS
OS Version: Sonoma 14.5
Node version (output of cardano-node --version):
```
cardano-node 9.1.0 - darwin-aarch64 - ghc-9.6
git rev 0000000000000000000000000000000000000000
```
I can pull out exact git revision, if desired, but it should be 9.1.0 tag.

CLI version (output of cardano-cli --version)

cardano-cli 9.2.1.0 - darwin-aarch64 - ghc-9.6
git rev 2fd3e13e9fa48a404429fd28252cecd723e021d5

IntersectMBO / cardano-node

[BUG] - `syncProgress` incorrectly says as `100.00` for Preview network (node 9.1.0) #5940