Interbank and leveraged names in among the offers just above 1.4300
We've hit 1.4303 but some offers just above the big figure are holding things back, for the moment. We shouldn't rule out some stops mixed in and they might be somewhere around 1.4310, maybe 1.4320, at a guess.
GBPUSD 15m chart
Update: Looks like 1.4310 was the stop level