Here is how Tesla retrofitted Superchargers in just 4 months

Tesla gradually retrofitted its Supercharging stations in Europe with plugs for the CCS Combo 2-compatible inlet on the Tesla Model 3. We don't have exact data, but it seems that the majority of stations were equipped with additional CCS Combo 2 plugs.

The progress of the transition from a single DC plug (compatible with Type 2 inlet in Model S/X, used also for AC charging) to dual DC plugs was presented in time-lapse video, released by fth (as of 31 March 2019).

From the video description:

"Tesla is adding CCS cables to the SuperCharger (SuC) Network in Europe, in preparation for the Model 3 rollout. This video shows the progress so far as a heatmap, where the SuC stations with CCS cables are given an approx 200km "influence", approximately matching the optimal range for longer trips (SuC "hopping")."

Model 3 owners in Europe can now fast charge at thousands of places - the localization of both the general CCS chargers and Superchargers can be checked out on the CCS Charge Map.

We assume that at some point in the future, Model S and Model X (of course also the Tesla Model Y) will be in Europe equipped with CCS Combo 2-compatible inlet for AC and DC charging.

Tesla-CCS Superchargers will enable Model 3 to charge at up to 250 kW. The other CCS DC fast chargers (like the 175 kW Fastned units) so far provided up to 125 kW of power.

Model S and Model X will be able to charge at up to 145 kW (after the most recent announcement) using Type 2-based plugs for DC charging.