It should be more clear in the Tips section that agaibh refers to both plural and formal singular :)
Hey! Yes, there was a mistake in a table and have edited (change wont have fed through yet). I'll look in more detail tomorrow. :)
That might partly answer my question, which was what is the difference between "A bheil ... agad" and "A bheil ... agaibh".
Is the latter formal, and the former more relaxed?
What is difference in translation twixt do you have a car and have you a car? I was marked as incorrect with the latter.