Apparently it did cause positioning issues last time around. One major problem was that GPS receivers calculate which satellites they expect to see in the sky b

Apparently it did cause positioning issues last time around. One major problem was that GPS receivers calculate which satellites they expect to see in the sky based on the current time and the almanac+ephemeris data, and at the wraparound some receivers started expecting all the satellites to be where they would've been 1024 weeks ago and completely lost lock. I think there were some problems caused by individual satellites wrapping their counts slightly before the actual GPS time too. Receivers which are started up after the 6th should be fine though.