I understand you not wanting to 'rock the boat', I don't like confrontation either. However, even if you choose not to complain, I would still inform management so they can't play dumb. Bring to their attention that you haven't asked for special treatment - even if those rights are protected by law - and you've pumped in your own time. Let them know that you will now be labelling it and keeping it in a wetbag or whatever, and most of all tell them WHY you're doing this now. I would probably get a copy of your rights re: pumping at work and email it across to them as well, just to let them know that you know what they're supposed to be doing.
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