Having trouble communicating due to the language barrier
I think the point is that knowing when this step occurs gives us an indication that progress has been made, and that the testing steps are in progress.
Kind of like a band announcing that they've finished recording to build anticipation for their upcoming album. Obviously the album has to be mastered, etc. but at least the fans can be pleased knowing that the final product is not too far off.
That said, what would be the benefit of knowing when the data is locked? Is that really the step that tells you the patch is coming?
I think maybe the reason they don't announce when the data lock was/is, is because if something major happens in the world of football they can put it in the update.
I don't think when the data lock happens has any bearing what so ever on when the patch will be released. If anything, the data update is a secondary requirement. As wally said it's about much more than data. I imagine they start preparing for the patch as soon as the last one is finished, and doing one bug fix could create a whole host of new ones many seasons down the line.