EGT lag in one cylinder after start

I’ve got a brand new 912iS that I just started for the first time after 2 years in storage (following the long-term storage procedures in the Rotax maintenance manual).  The engine started easily and ran a little rough at first, but quickly smoothed out and then seemed to run normally.  After shutdown I checked the lifters for purging, and found one that was soft and had excess gap.  So I followed the Rotax procedure to purge the lifters by running the engine again for 5 minutes at 3500 RPM.  After shutdown, I rechecked the lifter and it was now solid with minimal gap. 

All seemed well until I downloaded the data log from my Dynon Skyview and plotted it.  All engine parameters looked normal except for the #2 EGT (see graphs below).  For both engine runs, the #2 EGT lagged significantly behind the other 3 cylinders for the first 3 to 4 minutes, staying at only 200F for the first 30-40 seconds before climbing up into the normal range.  All of this was during the warm-up period, where the engine was being held at 2000 RPM.  Once the engine had warmed up, the #2 EGT seemed normal (though still a bit lower than the other 3 cylinders).

Any thoughts on what may be causing this?  A clogged fuel injector?  Spark plug issue?  Or is this not unusual given this is a new engine with less than 20 minutes total run time plus it was still warming up during this time?

Appreciate any help!