Good on you, dads always end up a bit left out when u breastfeed and expressing milk into a bottle is a great way to keep him included, plus it means u can get him to do the night feeds!! Breast milk lasts 48hours in the fridge. Yes u can freeze ur breast milk as long as it is before the 48hours have passed. It will keep in the freezer for 3 months. When u wish to use ur frozen milk allow it a good few hours to defost, simply take it out the freezer and put it in the fridge, once defrosted the milk will be 'good' for 24hours and can be warmed as normal once it is defrosted. Another good tip for breastfeeding babies who have the bottle is to lay them on their side, its to do with the flow of milk from the teat being much similar to ur breast. U literally lay the baby on ur lap facing you, u might prefer him/her on a pillow and pop the bottle in their mouth, then sit them up as normal to wind. It also reduces nipple confusion, which is a term thrown around when breastfed babies are given bottles and it basically means the baby getsconfused between the teat of the bottle and ur nipple. But in my experience its not a big problem, just make sure ur baby is well established at the breast first and then they should be able to go from one to the other quite easily.