If 1.5157 stands, GBP will see more upside correction.

The first idea that I want to stress out is that this upside movement is a correction and no a new trend (at least as far as now we do not have evidence to support the idea of a new trend).
If you observe the last up side piece of movement, is imposible to count it as a five, there for I have the theory that the second high of the last upside leg is the b wave of an expanded flat, and the next down movement is an extended 1 for a C down to end a x)) wave.
As the most long common proyection for this c under this circumstances are at 1.51579 I think the chances to bounce up again from that zone are pretty good.