as long as u get hold of the bird and get the rubbers off and into the clock i see no problem, if its on ets the same u would be moving the ets ring over the pad which would be in the loft, there is a rule (SHU) regarding ets that birds must be timed in the loft, but this is where it is timed, nothing about having to or where u must take rubbers off, i personally see no problem,