Describe the issue

The -loadblock command only reads the first few blocks from the file, but not all. At the next start with the same file, it takes the next few blocks, but also not all.

Can you reliably reproduce the issue?

Yes

If so, please list the steps to reproduce below:

1. Prepare new server for testnet (no blockchain, no database, no indexes)
   Disconnect from the network for the purity of the experiment (maxconnections=0 into zcash.conf)
2. Start the server with the command: zcashd.exe -stopafterblockimport -loadblock="D:\ProgramData\Zcash\testnet3\blocksBak\blk00000.dat" The server loads blocks 1-640 and shuts down. Recorded in the log file.
3. Start the server with the same command: zcashd.exe -stopafterblockimport -loadblock="D:\ProgramData\Zcash\testnet3\blocksBak\blk00000.dat" The server loads blocks 641-657 and shuts down. Recorded in the log file.
4. Start the server with the same command: zcashd.exe -stopafterblockimport -loadblock="D:\ProgramData\Zcash\testnet3\blocksBak\blk00000.dat" The server loads blocks 658-661 and shuts down. Recorded in the log file.

Without -stopafterblockimport, the same happens, only the server continues to work.

Expected behaviour

The server should load all blocks from the specified file.

Actual behaviour + errors

There are no errors in the console. It's okay.

The version of Zcash you were using:

Zcash version v3.1.0-rc2-d058568e0

Any extra information that might be useful in the debugging process.

debug.log