@Hshlevin 

You can find the latest firmware versio on the EN website:

https://www.tp-link.com/en/support/download/eap225-outdoor/v1/#Firmware

As for the issue of temperature, if it does not affect the use of the product there should be nothing to worry about, if it does, or if it feels overheated, it would be better to contact support directly.

  @Hshlevin 

It's normal for the 225-Outdoor to get warm to the touch, but should be warm like a hot sandwich, not hot like a mug of hot coffee :)  If you don't need all the radio power these units can put out, then feel free to back off the radio power and that will reduce heat.  My 225-outdoors are currently consuming 3.6W @ 53V each...and they are operating at full power.