As far as I can see, currently there are three issues:
New issue - 999 - clients game have crashed to desktop but show as 999 on the server, this did not previously happen on the existing old build
New issue (possibly to us) - server crash - https://dev.etlegacy.com/issues/1353
Old issue - WARNING: bad command byte for client XX - This causers clients to lag, warp, turn upside down etc
If you suffer from any of the above issues then please provide as much information as possible regarding what was happening at the time, both in game and your network wise, client version (open console and check version on right hand side) this information may help the developers regarding their build and TM regarding our infrastructure.
@Spyhawk