[Julianpms]

Being prepared and knowing what questions to ask does no harm. I would add to the list checking out provisions for travelling with pets, as the PETS passport scheme is also likely to be suspended, at least temporarily, in the event of a no-deal exit.
Keep an eye too on what happens to mobile phone (esp. data) roaming charges, which may vary by carrier and overseas country visited.
I would also recommend applying for an IDP now before the post offices become totally inundated on March 30 if the UK leaves without a deal.
Incidentally, I haven't lived in the UK for more than 20 years and didn't vote, so this isn't meant as any kind of political statement and I won't engage in any political discussion. But I am the author of a book on driving in Europe (now in its second edition), so I do follow the subject with considerable interest.