When these tweets were published, Mass Effect: Contact was quickly suggested by followers. I’m skeptical - on one hand, while thuway and shinobi602 are usually reliable industry insiders, they have been known to get things wrong. Mass Effect: Contact seems pretty believable - for one thing, most fans have suggested a ME game set during the First Contact War. That being said, Contact doesn’t necessarily have to be a prequel.
During PAX Prime last year, BioWare had a secret panel for a select few - exactly 21 of them, to be precise. Whatever happened during that panel wasn’t supposed to be leaked, but of course somebody did anyway.
Judging from that leak (which seems to lean towards a sequel rather than a prequel), Mass Effect: Contact could be about a future contact with another galaxy. I hope so, considering BioWare keeps using words like “fresh” to describe ME4 and the First Contact War is as stale as it fucking gets. This tweet, however, dampens the optimism a little.
(Can you tell I really don’t want a prequel)