Hi Les,
I can try that but I really wonder why the scheduling is made so complicated yet it does not work as intended.
May I ask your help to share the configuration for schedule for a new client? Perhaps I could start it from scratch for a new client and see how it behaves. I would like to do the following:
Daily incremental starts at 6pm.
No backup to be done from 7am to 6pm on weekdays.
Weekly and montly full.
Retention of the backup is 1 year.
There could many configuration need to be set, which I hope you could state here. Just share the configuration items and what value to set for each.
Appreciate it.

From: Les Mikesell <lesmikesell@gmail.com>
To: Prem <squirrelj@yahoo.com>
Cc: "General list for user discussion, questions and support" <backuppc-users@lists.sourceforge.net>
Sent: Wednesday, September 11, 2013 12:22 AM
Subject: Re: [BackupPC-users] Guide to set up scheduling in BackupPC

On Tue, Sep 10, 2013 at 12:55 AM, Prem <squirrelj@yahoo.com> wrote:
> Hi,
> Yes indeed, see below
> Because MyServer has been on the network at least 7 consecutive times, it
> will not be backed up from 7:00 to 19:30 on Mon, Tue, Wed, Thu, Fri.
> However, the backup was kicked in today at 8.05am.

Do you mean it started then or was still running at 8:05?

> What is really wrong and how to fix it for good?

Do you have enough time overall for all of your backups to complete?
The quick-fix is to start a full backup from the web interface at the
start of the backup window  (perhaps as you are leaving work...) and
you'll push the cycle to around that time every day.  But I don't
understand why one would start by itself in the blackout times so I
can't help with a better fix.

  Les Mikesell