Why does browser RTC sprint plan Taskboard view display stories and tasks from other teams and iterations?

Background

We are using RTC 4.0.3, soon to be upgraded to 4.0.7. We have RTC configured for 5 teams, and have numerous Epics contained within a release plan. Each Epic has numerous stories linked as Children under it; each story is assigned to one of the RTC teams, ready for tasks be be added.

Problem

When a team uses a browser to view their sprint plan (set to display stories and tasks assigned to their team, for that sprint) the RTC sprint plan Taskboard view includes all stories and tasks from all teams and from the current and all previous sprints. Each story and tasks which appears in error has a little left-facing arrow at the top.

Question

I am aware of this article and this article which imply my issue might be fixed in RTC 4.0.4 or 4.0.5 but in each article, one user's comment suggests the issues are not fixed afterall in later versions. Can anyone suggest whether they think my issue seems likely to be fixed within 4.0.7 or any other version or if there is another workaround?

Many thanks, Al