There is loads of spare capacity at T2 during the afternoons and evenings, but its gates are generally full in the mornings with long-haul. T2 can be very quiet on winter evenings, with just KL, AF and maybe KM due in and out. It wouldn't be such a bad idea to transfer a larger T1 user over to T2, but there'd be a gate problem until about midday.
I thought they were supposed to be extending T2 towards the M56 westwards, but that seems to have gone very quiet too.