P and O have changed their rules recently they will advise you of this when you get your pre embarkation information,.
P&O are quite open minded about taking alcohol on board to drink in your cabin,they do have the right to stop it but have chosen not to as yet.So yes in reasonable amounts it ok.to answer your next question they have a drinks order form in your cabin and you can order an assortment of af drinks for cabin use from that also they sell spirits and the mixers at one of the bars not cheap but it is Available and is charged in pounds to your account? hope this helps.
Yes you can take alcohol on board. There is no problem. P&O just reserve the right to confiscate it if the passenger seems the worse for wear. I agree spirits on the ship is not expensive, however the mixers are so we took some tonic and lemonade with us.
The drinks on board to purchase for your cabin are reasonable - we also like to have a drink in our cabin - before lunch - while we are getting ready for dinner and before bed. we have bought some drinks ashore if they are considerably cheaper but it is not worth the effort of carrying it to save just a few pennies. It is worth bringing you soft drinks/mixers aboard with you are these are very costly on board the ship.