Monks and nuns can not declare their chaturmas prior to samvatsari according to Jain agam "Kalpasutra".
If they do so, the house holds repairs, paints etc in the upashray or other places specified for chaturmas. Violence is involved in all these acts and the monks and nuns are held liable for these violence. Hence, they are not allowed to declare their chaturmas pre-samvatsari.
It is also said in Jain Agam (Shastra) that the monks and nuns ask house holds for accommodation. If they agreed monks and nuns can stay there for chaturmas. However, the present day practices are different. Shravak Sangh (Jain house holds) approach monks and nuns for chaturmas. If they agree they arrange for chaturmas. This practice is against Jain Agam.
Should all of us rethink?
Detailed post in Hindi
(Vardhaman Gems, Jaipur represents Centuries Old Tradition of Excellence in Gems and Jewelry)