MCT is irrelevant as OP is on separate tickets. The issue here is that he bears 100% of the risk of a delay. Thus, this is solely a question of OP's risk tolerance for having to purchase a new DUB-LON ticket on EI or some other carrier. Best bet here is to ask EI to change to the later flight based on its own change. If EI won't do that, I advocate either the later or much later flight which gives time for some downtime in Dublin itself.