
Maintenance begins at 2 AM PT / 5 AM ET / 9 AM GMT and is scheduled to run for approximately five hours, concluding at 7 AM PT / 10 AM ET / 2 PM GMT. During this period of time, Rare says the game's servers will be offline, so you won't be able to play Sea of Thieves at all, as it requires an internet connection even if you're adventuring solo.
This maintenance period shouldn't affect most players in the US given how early it will occur in the morning, but players in Europe will find themselves unable to play the game for quite a while. Another round of maintenance is also scheduled to follow early next week, on March 27. It will likewise begin at 2 AM PT / 5 AM ET / 9 AM GMT and run until 7 AM PT / 10 AM ET / 2 PM GMT.
Since its launch, many players have been experiencing a number of issues when trying to play Sea of Thieves, ranging from not being able to get online to not receiving gold after completing missions. Rare acknowledged these problems and outlined its plans to resolve them in a post on the game's official website.
Source: GameSpot