Today I started a new account and my mistake was to do it just before the daily maintenance window. I was on one of the tutorial missions and the 5 min timer started to tick for maintenance. There was no way to finish the mission before the maintenance started. After the maintenance when I logged back in the complete tutorial mission chain was gone (also no longer present in the Opportunity tab).
For me not so much a problem as I know how the game works, but for someone who is new this raises the bar to stick with the game tremendously. Basically you expect that a new player figures out how to raise a ticket (without the new player help channel). Or to play the game like it was 2010 without all helpful tutorial features.
Not sure if there is something which can be done about mission (chains) bricking during maintenance, but preventing it(or ensure that someone has to start over the mission after maintenance) would improve new player experience greatly.
Kind regards,
DumDum with some GumGum