Hi Steve
That will teach you to go upgrading stuff !!! In answer to your question Yes you have to go through the pairing process again. Normally press the pairing button and hold it for 3 secs while holding it put the key in the ignition and turn it on after 5 to 10 secs release the pairing button and you should see Bluetooth Pairing in the display, then search with your shiny new phone and enter the code.
If not you can use BMW 1.4.0 or INPA to force pairing. Remember your ULF can only pair with 4 phones when its memory is full you will need to clear it to be able to add another.
Dave