Before rendering prapatti, we used to celebrate Sarasvati puja with Sarasvati idols. After prapatti, we only perform Hayagriva aradhanam alone. What to do with Sarasvati idols?

In a Hayagriva aradhanam during Golu period, many households will include idols of Lakshmi and Sarasvati. It is a practice to offer flowers and other offerings along with other idols in the Golu. Sarasvati Devi is a subordinate of Hayagriva as per Svami Desikan.
“dAkSinyaramyA giriShasya mUrtiH
dEvI sarOjAsanadharmapatnI |
vyAsAdayO’pi vyapadEshyavAcaH
sphuranti sarvE tava shaktilEshaiH ||”
from this, it is evident that Sarasvati’s power is a minuscule fragment of that of Hayagriva’s power. It appears there is no harm to make the offerings to her from this perspective.