There are two releases of Avanti Phones, Version 1 and 2.

Latest software on 1 is sw_st30_0B_d2.hex
Latest software on 2 is sw_st30-r2_10_d3.hex

I recommend loading the latest on all phones.

You can't load version 1 on 2 or 2 on 1.

Depending on witch HEX file you use, only that version phone will show up.

You do need to have the correct processor. 7.39 I believe was the start of software download Plus the chip in the uld cards must be 1.05 or above.

Not positive on the chips or MPD version but if you are using MPD2 or IPEX you will be fine. Make sure you ULD chips are the latest to be sure with 2.06

I also recommend upgrading one or two phones at one time. If the upload process gets interrupted you will not be able to reload the software.