Hi Kevin,
IBM does not publish formal release dates for RTC. However RTC has an open dashboard showing the state of the development. If you go to the "What's happening" tab for the product, https://jazz.net/products/rational-team-concert/whats-happening#activity there is link on the right "See project dashboard". You can follow the development of RTC 6.0 on that dashboard. In the "Current RTC development plans" widget there is a link to the "RTC 6.0 Release Plan" which has start and end dates. This will give you an idea when they expect to ship RTC 6.0.
You find the dates for end of support for the team Concert products on our web site:
http://www-01.ibm.com/software/support/lifecycleapp/PLCSearch.wss?q=Team+Concert&scope=E614055K65406P51-R996242H58167H57&ibm-search.x=0&ibm-search.y=0&sort=P
As you can see no date has been set for the 4.0.x versions. However the support policy that applies is the "Enhanced" policy. This policy states that "Over the past few years we have aggressively moved many of the 2000+ products in our software portfolio to Enhanced ‘5+3’ Support – a minimum of five full years of standard support from the date the product release was made generally available by IBM, with the option to get support extensions for at least an additional three years following a product’s EOS date for an extra charge set by IBM."
I hope this answers your questions,
Simon
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