CLOSED Buy NVCoin transaction limit doesn't match Exchange Infrastructure level

I noticed an inconsistency with the Exchange Infrastructure upgrade. My current infrastructure level is 8/15, and the description says each upgrade permanently increases the personal maximum volume per transaction by +1.00 NVC. This means my current maximum should be 13.00 NVC.
However:

• Buy NVCoin: maximum is still 5.00 NVC
• Sell NVCoin: maximum is correctly 13.00 NVC

So the infrastructure upgrade appears to affect the Sell transaction limit, but not the Buy transaction limit.