If they keep running the events in order, then it would be Glacial Peaks next week. So we might get Ice Golem as a bonus, along with Snow Guardian and Frostling (which were the PC event troops). That's a total guess, though.
There are only 3 more weeks where PC/Mobile was still getting two troops per week. Aside from any oddballs that they might throw in (like Ice Golem), any bonus troops will actually start to cut into the number of weeks that we are behind.
With that and Silverglade being released we'll be only about 20 troops behind next Friday.