After lots of followup and re-routing and multiple versions for different Irish consulates across US citites and India, I finally reached out to Department of Justice who gave me email id of their Border Management Unit (BMU@justice.ie
They mentioned that there is no min. passport validity requirement for entering Ireland.
I think it is best to reach out to local consulates for a preliminary advise, but like my desperate case where I had no time for Passport renewal, you can reach out to BMU for expert advise.The following is what they had to say on the email:
The question of entry for any individual, visa or non-visa required, is determined by the Immigration Officer at the time of the individual seeking leave to enter the State. All relevant factors are taken into account with the principal ones being: the purpose of the visit or stay, the duration of stay, the ability of the individual to support themselves during their stay, and proof that the person will exit the country on or before the expiry of any permission given. Each application for entry to the State is assessed on its own merits. Furthermore, a permission issued by an immigration officer on a previous visit lapses once an individual leaves the State.Therefore it is advisable to carry any relevant documentation with you for presentation to the Immigration Officer on arrival in Ireland, even if you are returning following a previous visit. It may be noted that the powers granted to an Irish Immigration Officer are not unfettered. The Immigration Act2004 provides for the grounds on which an individual may be granted or refused leave to land at a port of entry.
In relation to your specific query regarding the length of validity of your passport, while aware of other countries requirements to such effect, Ireland does not currently require a specific remaining validity of a travel document. Regarding the visa waiver scheme, you are correct in saying that you may use your British Visa, however, it is best to be aware that you will still be subject to immigration control upon your arrival in Ireland and hence it is best to be prepared for same, (e.g. hotel bookings, return flights etc).
Hope this was helpful.