I'm not sure I understand the question, but I think it is: "I worked Easter Monday for time off in lieu, how much time off should I get?"
If so, the answer is that it depends what it says in your employment contract and/or what you agreed in advance with your employer. If your contract says nothing and you had nothing agreed in advance, then you can expect to get one day off in lieu - unless you can agree with your employer that you will get more - or even no days off in lieu, and simply be paid for the day you worked.