Question on 2385 Movement

[wach16]

I noticed something strange on my 25860 today and wanted the experts advice. I usually try and run the chronograph a few times a month to make sure the oils get some action. I always line up the chronograph seconds hand with the subdial seconds hand at 6 o'clock so they are in sync. Today after a few hours, I noticed the chronograph seconds hand was 4 seconds ahead of the running seconds hand. Has anyone seen this before? I could see the reverse happening (normal seconds hand running faster) if the vertical clutch disengaged by accident for a little bit but I am also not a watchmaker.

Also, I had a full movement service 2 years ago at APSC and had to send it back less than a year ago because it was running 20 seconds fast a day (oils dried prematurely was their response) and they serviced it again.

Thoughts?