I purchased four EAP115. They were sold as "as new" customer returns with full warranty. But the hardware version stickers did not correspond with what the controller identified. Please provide some clarification.

On the sealed boxes:
1. the normal small sticker states "Model:EAP115(EU) Ver:4.20".
2. To the left of the small sticker is a larger sticker that states "EAP115(EU) V4.0"
 
On the EAP Hardware itself:
the small sticker states "Model:EAP115(EU) Ver:4.20". There is no additional sticker or any other indication on the hardware itself that These may be v4.0

The Serial numbers on the small Stickers on the box and on the EAP Hardware itself are the same.

In the Hardware Omada SDN Controller running on the ER7212PC, all EAPS are identified as "EAP115(EU) V4.0"
The Mac Adresses shown in the Controller are the same as on the small sticker on the EAP Hardware.

One of the EAPS had v5.09 firmware (the latest for v4.0 harware) and three had v5.05. I was able to update the Firmware on all three to v5.09, although on one of them there was a glitch at first.

While I am happy to have gotten V4.0 versions, since I learned that v4.0 has more recent Firmware support than 4.20 versions,  it would be nice to get some clarification from TP-Link About the re-badging.

Do EAP115 HW Ver. 4.0 and 4.20 use the same underlying hardware, or was there are circuit board change done?

For my future planning, can I assume that these EAPs are indeed HW V4.0 and can be updated with firmware meant for HW version 4.0 going forward?