erm there's no ERM to break so no. it's a free floating currency. bond yields are up due to increased borrowing, currency is slowly lowering in value but hardly a soros moment.
There is no exchange rate mechanism to attack this time. There is support at parity with the USD, which was hit a couple of years ago. That is 18% lower from current levels. 'Rachel from Accounts' with her fake resume is currently in charge of UK finances, so anything could happen I guess:
Our department of Treasury is going to be run by a hedgefunder whose never managed more than 20 people.
This discussion seems pointless, in my opinion, unless you clarify the timeframe for the event and provide a precise definition of "collapse." Since there are no fixed pegs anymore, should a drop to parity with the USD be considered a collapse or just a normal fluctuation? Clearly, it’s not going to become worthless.
Even if it collapse the short sellers will bank money out of the market and move to another lucrative trading opportunity in my opinion.