### CONTEXT (Previous Events):
<system_output timestamp="8600.991594">Reading state information...
</system_output>
<system_output timestamp="8601.17896">Reading extended state information...
</system_output>
<system_output timestamp="8601.196089">Initializing package states...
</system_output>
<system_output timestamp="8601.799252">Writing extended state information...
</system_output>
<system_output timestamp="8602.052359">Building tag database...
</system_output>
<system_output timestamp="8602.530876">... [TRUNCATED TO SAVE SPACE] ...</system_output>
<system_output timestamp="8602.57975">... [TRUNCATED TO SAVE SPACE] ...</system_output>
<system_output timestamp="8602.583918">... [TRUNCATED TO SAVE SPACE] ...</system_output>
<system_output timestamp="8602.622827">... [TRUNCATED TO SAVE SPACE] ...</system_output>
<system_output timestamp="8602.670235">Reading package lists...
</system_output>
<system_output timestamp="8602.922857">Building dependency tree...
</system_output>
<system_output timestamp="8602.923994">Reading state information...
</system_output>
<system_output timestamp="8603.124027">Reading extended state information...
</system_output>
<system_output timestamp="8603.144273">Initializing package states...
</system_output>

### TARGET LINE (Extract and Classify THIS Timestamp):
<system_output timestamp="8603.639498">Writing extended state information...
</system_output>

Answer: 8603.639498, old event