Many argue that it is 820 now because 4.86 been introduced in 2012 (819) and it is now 2013 (820). What if I say 4.85 been introduced in 2010 (818) and it is 2013 (821) now? This logic can be applied separately for each version with different results. That is why I don't agree with it and why I am still waiting for thegreen.
To those trying to argue that the calendar is different from what we use now, I am pretty curious what alternative they had in mind. A thorough elaboration would suffice I say.
and again I am telling you that all infocards for 4.87 are written as if the date is 820. Dates in discovery don't track up real time for the mere fact that development process doesn't. Each version is an advancement of a year.