BMW is working on the mid-cycle update for its 3-Series, and we’ve already spotted prototypes for the updated version of the sedan. Now we have the first spy shots of some prototypes for the wagon, sold here as a 3-Series Sports Wagon.

Being a mid-cycle update, the changes to the styling will be minor. Look for new bumpers and tweaks to the lights for the exterior. Inside, new trim options and an updated interface should be among the changes.

Though yet to be confirmed, we hear the updated 3-Series will feature BMW’s new four- and six-cylinder engines based on the modular design first seen in the automaker’s B38 three-cylinder engine. The design calls for cylinders with a displacement of 0.5 liters, and the addition of fuel-injection, variable valve timing and turbocharging technologies.

A 2.0-liter four-cylinder engine based on the modular design, the B48, features in the latest MINI Cooper and BMW 2-Series Active Tourer and will almost certainly appear in the updated 3-Series. A 3.0-liter six-cylinder is also planned and should feature in the updated 3-Series as well.

Along with the introduction of new engines, we may see the current 328i and 335i badges replaced by 330i and 340i badges, respectively. In addition, a new plug-in hybrid model should be launched. The updated 328d, meanwhile, should keep the current model’s engine.

Look for a debut of the updated 3-Series sometime in 2015. Sales should commence towards the end of that year or in early 2016.