I spoke directly to Ilford some time ago about something similar involving differing development times for the film printed inside the box of the film and that quoted on the inside of the box of ID11. There response was to always refer to the times printed on their website and ignore the times in boxes with other Ilford material. (Nice to know)
The reason being when they have the boxes printed, they print thousands upon thousands at a time and occasionally development times do change before that run of boxes has been used up. That makes sense to me, so I always use the website figures.