Bosa started ~2014 and slowed down construction due to market conditions. It would have made the investment decision prior to that, so possibly around 2013. M2 is the only new project in EV since the recession hit. I'll believe anything new only when shovels are on site. I like EV, but even with hundreds of millions of public money it hasn't delivered that many new residential units or spurred development of privately owned land.
A project manager would have an opinion as to whether scope can be delivered on budget, and provide suggestions as to how to recover to budget. If CMLC is advising on scope addition, it would be a conflict of interest.
I'm surprised that CSEC would try to upgrade corporate boxes as that market is in decline as companies have been reducing their entertainment budgets for many years. Again, if CSEC sees potential in upgraded boxes, it should be able to charge more from them and fund the upgrades on its own. Tech changes make sense, but with the cost of technology almost certainly declining over time, it shouldn't lead to cost increases in a project that hasn't borken ground.