Presumably Boris cannot be arrested before November 1st, as it wouldn't be until we have left the EU without a deal that the law would be broken...
Which surely makes it a rather moot point...
I don't think he can be arrested anyway as under article 50 under EU law which takes precedence over UK law until we leave, any extension is the exclusive preserve of the PM and any UK law can't interfere with that.
Under the 1947 Crown Proceedings act crown v crown is specifically excluded or he could use Blair's 2003 Civil Disorder Act to suspend any act that he considers a danger to public order as his nuclear option.
This basically means we are leaving on the 31st under the current EU withdrawal act, unless parliament finds a way to stop this between the 15th & 31st of October. I suspect Dominic Cummings is well ahead of all of this which is why they are so confident we are leaving, with or without a deal.