OliWW
Seeing as GB doesn't officially become part of the easyJet brand until this coming Sunday, don't expect to see any orange until this coming Sunday.
The aircraft should have a temporary easyJet livery on them from day 1 of integration, but they won't have a full proper final easyJet livery on them for a couple of months.
It certainly won't be like the take over of 'Go' when Go branded aircraft were still flying the fleet for a couple of years after the final purchase went through.