Tapping Stasis does not end the "Stasis lock." Stasis does not need to be untapped in order to have an effect on the game.
Rule 418.4b
The effect applies at all times that the permanent generating it is in play or the object generating it is in the appropriate zone.
Tapping or untapping Stasis does not change the zone in which Stasis resides and therefore does not change the effect that it generates.
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If I may digress for a moment, compare this to a card like [card]Howling Mine[/card]. Under early rules of Magic, Howling Mine was what was called a "Continuous Artifact," which meant that it applied its effect as long as it was untapped. The type "Continuous Artifact" was later condensed into the encompassing "Artifact" type, but artifacts were "turned off" when they were tapped. Under current rules, artifacts remained turned on when tapped, except when the card specifically says otherwise, as with the current text of Howling Mine:
Howling Mine
At the beginning of each player's draw step, if Howling Mine is untapped, that player draws a card.