No sign of that though - as it doesn't pass the Forums - it shouldn't be affected by the closure of the roads there in any case!
The most common complaint about these ho-ho services seems to concern the state of their audio systems, as passengers break the earphone sockets with great ease, and regularity! If differences in the two companies' routes don't dictate which to take, it may be safer to trust the 110 Open line to keep their vehicles in a good state of repair.
With all the lines (even if their timetable makes no mention of the fact), at some point on the route the bus will have to stop - obviously they can't just circle for 10 or 12 hours - and generally the open spaces at Termini station are where they do so.
What happens then varies - at best it's just a quick change of driver, otherwise he or she may stay with the bus but take a mandatory break from driving.
And that leaves one with the choice of waiting maybe 15 or 20 minutes (though it feels like half an hour), or getting onto another of the same line nearer the end of its own wait - if one can squeeze in amongst its existing passengers!
The disruption is likely to be less with services whose runs are more frequent since there's more chance of getting away before the original driver finishes their break, but it's an annoyance, no matter what....
Peter
PS - there shouldn't be any reason not to do all three of your Day 2 sites - the Trevi's only a few hundred metres from the Pantheon.