It was originally to be above grade, then (I believe in late 2012) Metrolinx proposed tunnelling from Don Mills (under the Don River) so that it could be grade separated all the way from Mount Dennis to Don Mills which is a major hub. If they were to keep the Leslie stop it would now have to a full underground station and they said the low ridership numbers couldn't justify the $100 million plus for a full station so they proposed eliminating Leslie and having no stops between Laird and Don Mills which was always to be underground. Metrolinx got too cute by half though, and tried to sell the change at public meetings as being necessary because they COULDN'T build the launch shaft at Brentcliffe. They said it was too narrow and to close to Scenic condos south of Eglinton and digging might disrupt the condos' foundations. Of course, as we've seen, that is pure bull as they have built the launch shaft there but perhaps it took longer in order to protect the slope from collapsing. Metrolinx needed the public meetings because the proposed change would need an EA amendment. They thought they could just slide it through quickly and they'd be away. The Leslie condo YIMBY's fought loud and hard (all 12 of them) and with LPOA's and especially Robinson's voices they put up such a stink that Metrolinx said they couldn't wait any more. In spring 2013 they reverted to the original plan. By not being honest, Metrolinx lost all credibility and so therefore lost the chance to build a much superior tunnel to Don Mills. At one of the few meetings where actual engineers attended, a Metrolinx engineer told me he was disgusted that they weren't launching at Don Mills. It would have created much less chaos on Eglinton between Leslie and Brentcliffe, would have been easier to build as there is a lot more room for a shaft at the Science Centre lot and in the long run would have created a much better LRT line with full grade separation through to Don Mills (and maybe someday a relief line interchange there).
Because of headway differences between the in-median and underground portions of the LRT, every second train will short-turn at Laird even though it won't have near the riders that Don Mills will. Ironically, the Leslie condo dwellers will probably be far better off bussing to Laird station with twice the frequency of trains then waiting twice as long, after a longer walk, in the elements, for a train at their hard-won Leslie stop.
Ridiculous.