Hello Mridhula,
Apologies, this is my 3rd attempt at replying to your post. For some odd reason , when I posted through my phone, it did not get posted, not sure why.
A "Sandhya Aarti" or "Saandhya Baati (Light)" is performed every day, by one of the ladies in the house (usually the bahu/s), where a diya/s is lit up at dusk(sunset), to ensure that the house is never left in the dark.
The diya/s is later on blown off, to ensure that it does not cause any harm or accidents. But a home must always be lit up and never left in the dark, during dusk/sunset.
One other rasm that kind of completes the wedding is the 1st rasoi that the bride does where she cooks a dish and serves it to the family specially the elders. It is called "Bou (Bride) Bhaat (Rice)".
The makers are probably saving this rasm for the actual RuNak wedding or we can assume Jhanak does this every day any way 
We recently celebrated 'Poila (First) Boishakh ' , which is the 1st day of the Bengali New Year on the 15th of April, not sure if the makers will show this as an event in the future !
Also,even in this day of whatsapp and emails, the elders of the family would visit the neighbourhood and the invitees personally, to invite them for a wedding with a wedding card, requesting them to part of it and bless the newly weds. It is a gesture conveying that your presence is welcome and we would be obliged if you attend it - this was shown by the makers.
Kolkata is usually extremely hot and humid, and during our growing up years, when AC was not common, the printed cotton salwars that we see Jhanak wear, would be a comfortable and bearable choice though not necessarily a fashionable one 
Lastly, I leave you with 3 Bengali words used in the recent episodes with their explanations-
1. Ani says "Woha uska Bor (Groom) Boron (Welcome) ki rasm chal rahi hai" - When the Var (groom) comes for the marriage, he is welcomed by the Bou (Bride's) family.
2. Shrishti says when Jhanak garlands Ani by mistake "Bhul o mat tum Chhadna Tola mein khadi ho" - It is the canopy under which the exchange of garlands take place.
3.Bipasha says "agar yeh shaadi nehi hui toh tum Lagna( Auspicious Hour/Time of the Wedding) Bhrasta (Vrasht or Damaged) kehlayogi" - A concept in the olden days where a bou (bride) stranded at the marriage mandap would be tagged so.
After reading Sohini's post on all the rasms in the bengali shadi and how every rasm was performed by Ani and Jhanak. I am thinking this diya scene was just for that.
Ani has called her his wife not once but twice, toh madame is being the ghar ki bahu and doing the first arti as the bahu. Shadi samapt hui.
Sohini - can you confirm?
In essence, are the makers showing this is the RuNak shadi without it being the shadi?!
CID
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