No expert and have'nt managed it yet but.
Yeah you can get ambits on ebay.
You could always ask the seller when it was last on line .Then you would know if it had the update.????
I got a couple with updated( buggered a few myself!!0
Took off tsop. re programmed chip with dump from 120 and soldered tsop back.
Still no joy???
Should i tell you this as i got a few from there.
Funny thing was. Someone put a selling point that the ambit they was selling was in perfect working order as it was on line a week ago.
Bet they wonder wonder why no one bid on it???