EDIT: Blue confirmed:
http://us.battle.net/wow/en/forum/to...4156?page=2#31
PSA check your accounts.
I noticed both of my base alternate accounts have been upgraded to MoP for free.
EDIT: Both of the alt accounts were RAF accounts so blackblade may be correct.
Thanks, blackblade
This must be the case. Both of my alt accounts were RAF accounts. Ill update my OP. Thanks
EDIT: Both accounts say "Standard Edition".