Hi Mick in OZ
Those are lovely bees, look like Buckfast Superbee, just like mine! I guess it's not that swarm I lost year flown all the way to you!!!
if they are Superbees you are very lucky, mine are fantastic, very placid, and believe me I need placid bees, (see my other posts!) Mine overwinter really well explode into brood rearing about now and produce vast qauntities of honey through the season.
Take care of them and they will reward you well