My hats off to "leolaohoo" FYI for others:Following instruction is quoted from http://www.cisco.com/en/US/docs/wireless/access_point/conversion/lwapp/upgrade/guide/lwapnote.htmlFollow these steps to revert from LWAPP mode to autonomous mode by loadin...

Yes, of course; as soon as I get access to my computer. I don't know if I can do so by replying from BB.

Yes, it is exactly my case. Returing wrong models will take a while. If both hardwares are the same I will just change software. I was afraid that Cisco won't allow users to do that.  Thank you so much for your time and info.

Thanks, leolaohooDoes it mean that I can't just replace IOS?Are functions restricted by firmware?