"BioWare has put Mass Effect on hiatus"

There probably won't be. But why quote pale copycats when you have the awesome original offering us the veritable wealth of accurate information cited already? 

Never trust any drivel written on media sites that don't have direct quotes from the horse's mouth.

Can you handle the truth? If you can't, don't read below. It'll be like ripping off a Band-Aid.

If EA is shrewd, like R* shrewd, they'll pull a GTA V and focus on online only to make as much money as they can from here on out off of MEA's multiplayer. They won't expend one dime more on story DLC (presuming development didn't get far enough) while never directly stating that there won't be any story DLC ever. As long as they don't promise (but fail to deliver) story DLC, they'll fare better than R* has with let-down SP campaign fans, whose backlash to R*'s broken promise of GTA V story DLC has yet to materialize. MEA's campaign is twice as long as any single campaign from the OT already, so who can self-righteously complain about not getting story DLC, as far as EA is concerned? The overwhelming majority will never care and will keep feeding EA $$$ because the multiplayer is all that they really care about, not the campaign. The end.

Edmonton did the original trilogy, yes, while Montreal did the multiplayer and the Omega DLC for ME3.

However, it is hard to tell whether this is true downsizing or just the usual process of big game studios reshuffling staff after getting a product out. Right before a launch a studio will often have a lot of people working on a game that are needed more urgently on other projects once launch is completed. Edmonton has their new IP "Dylan" and most likely a new DA game. Austin is handling SWTOR as well as "other new, unanounced projects", according to the Bioware website. EA's Motive Studios is also in the same location as the Bioware Montreal stuff, so it's quite possible that staff could also be temporarily moved to help with their projects.

Bioware Montreal will now only have to handle keeping the ME4 multiplayer alive - and probably get out some DLC because, let's all be honest here, this is EA. I doubt they'd let a game get away with no DLC. Also, even DA2 got DLC, and that launched to worse reviews than ME:A.

DLC the way it is made today is often already planned and partially prepared at the same time as the original game. Not always to great amounts, of course, but even then you generally don't have to code Frostbite anew and staff the world with dozens of new character models (maybe a couple new key characters at best), don't have to build too many completely new sets, etc. It wouldn't be impossible for a skeleton crew to handle this.

I mean, it's all speculation at this point, of course. E3 will probably tell us more on that front.

A studio that is not trusted to work on new IP's are usually given the patch and DLC work for existing titles. 
Makes it more likely that it will be Montreal that make the Andromeda DLC's.

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