Top tags for data set brexit which ranges from 2017-03-31 until 2017-04-05 and contains 745,843 tweets  (and counting).

brexit (230076), gibraltar (21720), article50 (15901), eu (11122), scotref (7186), uk (6232), trump (5345), indyref2 (3762), ukip (3656), poundtoeuro (3389). So for the last 3 days and potentially 4 the debate on Twitter is dominated by Gibraltar.