Q: I read the discussion of preaching while seated. We have two elderly and frail priests who are requesting a stool to sit on while at the altar. Is that allowed?
A: The rubrics do not account for such an unusual circumstance, so they’ll offer neither encouragement nor obstacle.
It’s quite common to meet some clergy who can no longer genuflect, and they bow reverently to the Blessed Sacrament as an alternative. Again, the rubrics do not provide anything on this, but charity prevails.
The same, I’m sure, would apply in the case you present.