See GE results 2010, 2015 and 2017.
1. When LD do well YOU do badly.
2. When UKIP/BREZI/YORKIES do well, the TORIES suffer, LAB is OK.
JC's hard Brexit policy is boosting LD. (see 1)
If Brexit happens, the BREZIS disappear. (see 2)
Join the dots, Caroline.
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A) JC switches to remain and you get back the Labour defectors from LD / GRN... plus a few Tory remainers.
B) Brexit is cancelled, so the Brezis don't disappear, but hang around cannibalising half the Tory vote.
Wake up, wise up, GTTO.