not sure if it's already has been included yet, but in 1.1.18 SSLv3 is still available for apache
I think it is not a i-MSCP function, this is a task of a sys-admin :).
If I remember correctly i-MSCP don't edit the ssl.conf. So, if you edit your ssl.conf, which you should do, the changes are untouched by i-MSCP.
hmm, in proftpd and postfix it has been fixed,
therefore I was wondering because a previous deactivation was overwritten by an update
it might have been forgotten
As I wrote above, the ssl.conf is not touched by i-MSCP. The configs of proFTPD and Dovecot are generated by i-MSCP, so they changed it.
If I remember I have deativated SSLv3 in Apache middle of October. After taht I have installed 2-3 Updates of i-MSCP. The ssl.conf was not changed during the update. So, I see no problem.