Sorry to say it but customer retentions will tell you anything in order to keep you. Unless you have it in writing, it's worthless. I wouldn't place any bets on the STM being dropped as something needs to be done about the muppets that leech their connection 24/7.
When I phoned up recently, they tried to persuade me that their V+ service was much superior to Sky+ and worth paying more for because of the HD capability. When I pointed out there is bugger all HD channels on VM she started waffling on about Ofcom and getting them to force Sky to share their content at better prices, yada yada yada - it was just all waffle. When I asked if they'd be reducing the cost of V+ as a result of Ofcom forcing the content to be cheaper at this mythical date in the future, I got no specific answer. Funny that.