Over 100,000 have already signed, which pretty much guarantees a parliamentary debate. Is this a record in so short a time? A few more signatures won't hurt though.
https://petition.parliament.uk/petitions/116762
Apparently you can't stop the Post Office delivering the thing as the opt-out process takes about six weeks, and registering an opt-out could also block stuff you actually want. Interesting though that the printing was done by a UK subsidiary of the German Post Office, and is a company which itself regularly receives subsidies from the EU. This leaves a casual observer wondering exactly how the £9.2M order was actually placed.
Also interesting that the pamphlet - which purports to be the balanced advice of an elected government - was produced entirely behind the backs of several senior cabinet ministers of that self-same elected government. I don't think Desperate Dave has heard the last of this; and maybe needs to fly back to the sunshine for more time to think?