bash remove string for logs

Hi, I have the log file, each of the line first few string "<space>10.99.9.99<space>" need to remove and the IP address could be different for each log files, I need the script to count the character to remove for each line

<space>10.99.9.99<space>2017-03-27 23:44:49 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

After process remove the string the script need to append date time from first line of the log to the top the log file

example :

#Date: 2017-03-27 23:44:49
2017-03-27 23:44:49 xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx