CUD_INPUT_ERROR for some waypoint names

[Madman1]

I've noticed that if I name a waypoint certain names I get CDU_INPUT_ERROR but not other names. For example if I name a waypoint 2S3 I get the error message but if I name that exact same location TWOESSTHEREE I do not get the error. What gives? Is there some list of alphanumeric combos that the A-10C's CDU is forbidden to accept?

Edited October 11 by Madman1

[Madman1]

See example attached. First I tried some actual targets, all worked. At the end I took a random location, tried to name it 2S3 and it got CDU_INPUT_ERROR; made a new waypoint at that exact same location as that one but named it TWOESSTHREE instead, got accepted. This is FUBAR.

LastMissionTrack.trk

[ASAP]

Waypoint names can't start with a number