Question: Is there a way get the list of changelists after a particular changelist for a particular branch?

```
p4 changes (some flag ?) (CL#) //depot/project

```

Answer: 
```
p4 changes "//depot/project/...@>nnn"

```

where nnn is your CL#.
If you're into Perforce Integration, and you need to get the next CL to Integrate (the CL right after the last one you've integrated, say @12345), try this:

```
p4 changes "//depot/branches/branch_name/...@>12345" | tail -1 | cut -d ' ' -f 2

```