I just tried a 5k workout with PacePro enabled (265 with latest firmware). It computed intervals of about 7m02, 6m46, 6m28, 6m14, 6m00 split paces and it did show the correct graph when I started my run.
However, right at the start I heard the instruction: "Next pace target 6m44.", which immediately was repeated: "Next pace target 6m44".
The 1k progress bar did not advance and the ahead/behind stayed at 0:00.
I can't recall the target pace I got after 1k, however from 1k to 2k the progressbar started working. Ahead/behind stayed at 0:00, though I was ahead by at least 20 seconds by now.
After 2k, 3k and 4k the progressbar reset and worked as expected and I did get the correct pace instructions. Yet ahead/behind stayed at 0:00.
After 5k, I finished in 31m30s, 1 minute ahead of my 32m30s target, I saw a screen: "556:30 behind" or something similar.