Will the invocation of article 16 affect British citizens and their dependents in the Republic of Ireland?

Just to expand on the subject:

Article 16 is part of the Northern Ireland protocol, the section of the Brexit withdrawal agreement which deals with the North. If triggered, it would essential turn things in the direction of a no deal Brexit.

If the EU or the UK invoke article 16, will this affect non EU dependents of British Citizens living in Ireland who already have a stamp 4 (given to them under the rights guaranteed in the withdrawal agreement)? Or is this part of the withdrawal agreement set in stone and entirely unaffected by article 16?

If anyone can provide clarity on the above it would be greatly appreciated.

It's a hypothetical question. It hasn't happened yet. Nobody knows what consequences will be there, but there will be retaliations from the EU. Whether that will be restricted to trade only, or if that will impact British nationals & their family members' residence rights, nobody knows.