I'm the absolute past mistress of storing/freezing milk and had various systems. I followed the nicu guidance
6 hours out at room temp (no more than 20 degrees)
6 days in the fridge
6 months in the freezer
None of mine ever had a hint of d&v so I'm comfortable with that regime - however, it is entirely predicated on having optimal storage facilities that I have control of (e.g. my own fridge with clear temperature controls and temp display) i.e. not randomly assuming that milk will definitely freeze on an aircraft
Also, if you're away, how do you even freeze freezer packs? Prrsumably guving them to the hotel but most hotels aren't very keen to store or freeze guests' food/utensils as the vast majority have very strict food hygiene protocols for what is taken in and out of their commercial fridge/freezers
Plus the mini bar fridge in the hotel room doesn't reliably chill down to the same level
as a domestic fridge so notguarabteed that the milk is being stored correctly
Honestly, the whole thing is bogging and so risky