How does one go about conveying their feelings to a friend group in a respectful way in person?

Hello everyone,

I have a friend group that I’m a part of that reached out to me via text saying that they don’t appreciate or like the fact that I usually come and go whenever they make plans for us to all hang out during the day when they’re in town as well as my common lateness to events they plan. For example, when they came into the main city that I live in that’s a known tourist area, they planned a lot of activities for the entire day that they would all go to together and invited me. I went with them, but – and this is my fault for not conveying that I would do this – I arrived at the first location pretty late (which is on me) and would go for certain events and then leave because I had something else planned that evening. Apparently my leaving when they planned the whole day for all of us to hang together they saw as rude.

All of what they said is valid and opened my eyes to how my lack of communicating these changes in advance would cause some strife, but the thing that’s bothered me about this is the fact that they designated one person to reach out to me to speak on their behalf via text weeks later instead of speaking to me about it in person all together in the moment. I felt rather blindsided about it.

How would I go about conveying this issue when I see them all in person? Should I mention it the next time I see them alltogether as a group? I also want to provide them with some context to my lateness is usually due to my ADHD time blindness that I am working on improving, not to excuse my actions, but to at least give some reasoning behind it so it’s not like I’m like this because I want to be. Thank you.