A warning for walkers using GPS devices that were made prior to 2010. The date format used in the older specification for GPS devices runs out of digits this April 6th. The specification was changed some years back and all more recent devices that use the ‘ICD-200/IS-GPS-200’ specification will be able to cope with dates after 6th April 2019, but it is unclear how some older devices may react to the problem. The date stored by older GPS units is likely to fail after that date, and revert to an earlier date. The GPS may well continue working fine apart…