Two quick data points:

JER flight arriving at T5 A19 to T3 CX lounge: 26 mins, going airside route. Got lucky and was the last person on a bus that was leaving immediately. Next was six minutes behind.

T3 flight arriving at gate 23 (I think) to GF via First Wing: 29 mins, landside route via HEX. T3 was heaving on arrival and a lot of people were heading to connections, so decided to go landside as I had plenty of time.

Both very solid, would have been better without a 25 minute wait for the air bridge to be attached on the T3 arrival!