I don't think this necessarily answers your question but before I went back to work, I started transitioning DD to childcare slowly. 1hr Building it up to whole day. During that time she (who also doesn't take a bottle) had EBM that I had stocked up but would take 10ml initially (now she'll take abt 50ml & prefers just food). She actually 'self weaned'. I thought I would need to express at work but I didn't because she just didn't want it even when I did because i guess it's not the 'real thing'. So during the transition period, my boob also got used to it. Initially it was uncomfortable, and I had to just manually express a bit for comfort relief. But it does get used to it fairly quickly. Hope this helps. Good luck!