Break in residence in year prior to application

Hi there,

I am writing this on behalf of a friend who is hoping to apply for citizenship on the basis of having lived in Ireland for 5 years (stamp 1).

My friend has been living the whole time in Ireland however early this year, due to a change in visa-type, my friend has a gap of 1 month or so missing. This is due to the change in visa type however he was not issued any letter or backdated stamp from GNIB. Due to this 'break' in residence, the online residency calculator deems him ineligible even though he has, in fact, been resident here the entire time.

Any information for him would be greatly appreciated.