In the past, either if we were staying where supply was somewhat inaccessible/intermittent or whatever or if we were going away for an extended period, we have often frozen milk. We have done this up to two litre container size (full) but mostly limited to semi skimmed. There have never been any adverse effects. The milk has tasted and behaved fine, lasting until we finished it. I have a vague recollection of at some point having frozen a litre of whole milk which showed slight signs of separation and (if I remember correctly) we gave it a shake and never noticed anything adverse after that.