How did you obtain your Stamp 4? If you obtained your Stamp 4 via IIP, you can come to Ireland at any time you want. Otherwise, generally speaking you cannot leave the state for more than 3 months in a year.
You also need to inform INIS in advance if you are going to be out of the state for longer.
Of course COVID-19 restrictions may give you some bargaining chips, but 14 months is still a very long period of absence. Have you been paying taxes during these 14 months time?
Either way, you would need some good explanations at the port when you come back. Even if they allow you back in, you may still have big troubles when you try to renew your stamp.