Almost all receivers from that vintage can accommodate one rollover with no problems. But if restarted cold (after any power off cycle where data memory is lost assuming rollover flag or extended week number is saved in BBRAM) after 19.6 years since its birth, the date will be 19.6 years behind.
On some receivers you can provide an aiding message to set the correct date if you find yourself in the condition above.
Refer to u-blox 4 documentation for details. (I don't have u-blox 4 documentation)