From Middle Egyptian, this feminine singular form was generally used for the plural. In Late Egyptian, the masculine singular form was used with all nouns.
špss kꜣ pw ḫnt(j) ḏdw wr ẖrt m ḫm nb hnw m ꜥnḏtj ḫnt(j) ḏf(ꜣ) m jwnw nb sḫꜣw m mꜣꜥtj bꜣ štꜣ nb qrrt ḏsr m jnb-ḥḏ bꜣ rꜥ ḏt.f ḏs.f
He is noble of ka, this foremost one of Busiris, great of possessions in Letopolis, possessor of acclaim in (the nome of) Anedjti, foremost of provisions in Heliopolis, possessor of remembrance in the Two Truths (Hall of Judgement), the secret ba, lord of the cavern, sacred in Memphis, the ba of Ra, his very body (lit. his body/self of himself), […]
References
James P[eter] Allen (2010) Middle Egyptian: An Introduction to the Language and Culture of Hieroglyphs, 2nd edition, Cambridge: Cambridge University Press, →ISBN, page 125.