just been reading this bill came across this bit.
‘If the European Council proposes an extension to a different date then the Prime Minister must accept that extension within two days, unless the House of Commons rejects it.
not an expert on it but surely that would be leaving it open to the bill being refused royal consent ,as you cannot have an outside body telling the government of the UK what to do as a precedent making this bill open to refusal at that stage ?
might be reading it wrong but that looks like that at first glance.