The Scottish National Party, which is committed to holding a referendum on the independence of Scotland from the United Kingdom, won a majority of seats in the Scottish Parliament yesterday. See:
It was unexpected that a majority of seats would have been won by any one political party in the Scottish Parliament becuase its seats are allocated with elements of proportional representation. In order to win a majority of seats, one party would need to get close to 50% of the popular vote, if not more, in an election.
As the Scottish National Party is the only party in Scotland capable of winning a significant number of seats that would support holding an independence referendum, it was unlikely that any referendum bill would have been approved in Parliament, thus preventing a referendum from being held. That significant obstacle is now removed.