plane upgrades and replacements delay

[topeverest]

To all the allied players out there. What is your experience in aircraft upgrade delays and repalcements.

I have been watching one particular unit I have targeted for upgrade, and it has been two weeks, depite available aircraft and beaucoup supply. I can't seem to identify anything different about this particular upgrade, but it will not upgrade. Are there any particular circumstances that work beter or worse, because I can find no reason for this one.

What horror stories are out there. Do planes on carriers have to be removed to upgrade. Does being out of range of your HQ slow or prevent upgrade? Do certain bases or types of bases have penalties for upgrades and replacements.

What am I missing?

[Barb]

Upgrades: Upgraded units had their repair rates purpotedly lowered - As mechanics have to make new planes combat ready and crews to made familiarization flights, and so on...

Replacements: You cant draw them only after delay from previous draw - No more each day drawing new planes into squadron. More reflects the reality.

[findmeifyoucan]

Also if you are too far from your HQ the air unit will not be able to upgrade. Sometimes you will get a message saying that you are too far from your HQ.