We have a private guide reserved for tours of the Vatican and the Colosseum at the end of May. Our guide is recommending an afternoon tour for the Vatican to avoid the morning crowds, and the next morning for the Colosseum Although he is highly recommended, he is not one of the Vatican approved guides who can enter between 8 A.M. and 10 A.M. My husband's biggest concern is waiting in line. I know the lines used to be shorter in the afternoon, but I wonder with the new entrance policies if this will still be the case. Due to the public hour to enter being later, the crowds inside may also be larger in the afternoon.
Any comments from those who have recently visited would be appreciated. My husband and I have been to Rome and these sites several times, but it is a first trip for our son and daughter in law.

We found the lines to be shorter in the afternoon when we visited in early March. There is a recent thread called something like Advice on the Sistine Chapel which confirms that this pattern still seems to hold true.

I was just in Rome for Easter Week. We toured the Vatican on Holy Thursday with Angel Tours. It was extrememly crowded, but that is what I would have expected given the timing of our visit. Our tour was in the afternoon and we did not have to stand in the main line, but we did have to go thru security; everyone does. We waited less than 30 minutes overall.

Thanks for the replies. I think we'll stick to our guide's suggestion. I doubt there is ever a time it won't be crowded since we by necessity are traveling during the busy tourist season. It's worth the wait in line.
I am so grateful for the generous sharing of information on this site!

The end of May has plenty tourists in Rome.
I'm sure the guide will probably get you in with little wait time,it's his job.
Assuming that you get there between 12 and 2, my experience is that there is little lines.
It's good to here from recent travelers that this remains the same. Until the heavier season begins (which really starts tomorrow) it's hard to say how the new rules impact afternoon lines.
If I had to guess,I'd bet the mornings will be worse and the afternoons and 12-2 better. Mainly because many of the our groups that are now going in before ten used to (in longer day seasons) take advantage of the shorter afternoon lines.