The catch-up can wait
The third part is for the long stretches, the names from chapter 16 and the back of the list in chapter 18. A year, three years, a friendship that's gone from weekly to nothing without a fight. Here the catch-up is the whole obstacle, and the method is to refuse it.
Don't do the catch-up in a message. A year of news doesn't go in a message. It goes in a room, over an hour, where it's a pleasure. The message that reopens a long stretch says nothing about the year. It says one thing, or asks one thing, and it's two lines like the rest. "Just found the photo from the Lakes. Are you still in Bristol?" If you want to name the stretch, name it once, lightly, and don't apologise for it. "Been far too long. How are you?"
One thing, or a date. The pick-up message is either one thing you thought of, which is chapter 20's line, or a date. "I'm in Bristol on the fourteenth, any chance of a coffee?" A date is the stronger of the two, because it converts the pick-up into a plan in one move, and a plan doesn't need a catch-up before it, it is the catch-up. If you can offer a date, offer it. If you can't, one thing, and offer a date in the third message.
The third message. The pick-up goes, they reply, and the third message is yours, and its job is the room. A call, a coffee, a walk, a visit. Chapter 11 said the message is the door. For a long stretch the door has to open onto something quickly, because a long stretch handled entirely by message becomes a new stretch. Two exchanges, then a date.
Expect it to be easy. Chapters 6 and 16 said you'd underestimate how welcome this is. That's not encouragement, it's the finding. The person you haven't spoken to in three years is the one most likely to be glad, and the least likely to have been expecting anything, and the reply will come, and it'll be warmer than you'd have guessed, and you'll wonder why you waited. Then you'll be in a room with them, and ten minutes in it'll be fine, and an hour in you'll have covered the three years without trying, because that's what rooms are for.
One a week, not the list. Don't work through the thinned list. Pick one name a week, or one a fortnight. The list isn't a task. Most of it can stay fond and quiet. The pick-up is for the two or three names that still give you the small heavy feeling when you see them, because that feeling is telling you which ones aren't finished.