Can't upgrade/replace motorbike? 1.03b11

[ydmatrix2]

When having a newer model: infantry can be upgraded (personnel stays in place, equipement upgraded), buggies/tanks can be replaced (old equipement sent to SHQ, new model sent to unit).

Neither option works for motorbikes?
The upgrade button is greyed out, the replace button is shown but the next window shows no target models to replace with (although "Harley II" model exists).

[zgrssd]

If I understand int correctly, it works same as artillery or tanks:
1. Build replacements in the SHQ
2. Hit replace.
3. Have the new models with old XP in the unit
4. Do whatever you want with the old models with green troops at the SHQ.

[ydmatrix2]

You're right, I have missed that for some reason.