Calculating the date of Easter was from the earliest centuries a source of schism between the Western and Eastern Christian Churches. But the inconvenient fact is that however calculated it is a ‘Moveable Feast’ which in the Western Christian Church means that it can occur at any time between 22nd March and 25th April.
Anthony J Sargeant notes that in 2018 the Church of England will celebrate Easter on 1st April while his Greek Orthodox friends will do so the following Sunday.
The Resurrection of Christ (which is celebrated on Easter Sunday in the Christian Church) by Murillo
There is no particular problem with this, people are free to celebrate festivals of any religion or other mythology that they choose to follow whenever they so choose. But there is no convincing argument for having a public holiday on Easter Monday, a day which has no religious significance in itself. It is simply ‘the day after Easter Sunday’. (N.B. The sensible Scots do not have a public holiday on this day – though they do on the preceding ‘Good Friday’)
After all there is no longer a public holiday on ‘Whit Monday’ (that is the day after Whit Sunday, another ‘moveable feast’ related to Easter). That public holiday was transmuted into the Spring Bank Holiday and that always occurs on the last Monday of May.
Thus if it is thought desirable to have an ‘Early Spring’ public holiday why not have it on, let us say, the first Monday in April? It could also be associated with a public holiday on the preceding Friday (replacing ‘Good Friday’) thus creating a long weekend at a fixed point in the calendar that could be more easily be scheduled into business and educational timetables.
To reschedule public holidays in this way has no particular religious implications. Those who so choose can still celebrate Easter (or any other festival) whensoever they choose.