Worth considering the bulkiness of Your BB area, considering its a TT bike. My Felt AR has a fat arse BB area. So I need to pull my cranks off to Access the battery.
The rotor issue was for a steel bike, not a TT bike.
The TTbike has a steel bsa bb bonded into the carbon frame (quite clever). The di2 wires will run under and around in, back up into the seat tube. The seat post comes out and battery gets put down inside. Loads of space in there tbh.
Ta. Think I'll just use the srm for TT bike anyway now.