The hundred and eighth lotus (Rama's untimely worship of Durga)
Unable to beat Ravana while the Goddess protects him, Rama wakes her in autumn, out of season, and worships her for nine days. In Bengal she hides one of his hundred and eight blue lotuses and stops him as he reaches for his eye; in the Devi Bhagavata Narada teaches him the vow and the Goddess appears on the eighth night.
Ravana's praise wins Ambika, who sits in his chariot with him in her lap; Rama throws down his bow. The gods prescribe the untimely waking and Brahma wakes her in autumn. Rama makes a clay image, ties the Navapatrika, sings the Chandi, and worships on the seventh, eighth, the joining and the ninth. She does not come. Vibhishana asks for 108 blue lotuses from Devidaha; Hanuman brings them; the Goddess hides one. Hanuman finds none left. Rama, called Nilkamalaksha, resolves to give an eye and lifts an arrow; Katyayani stops him, says Sita was never truly taken, and grants him victory. He fights on the tenth.
Narada comes to the grieving Rama singing the Rathantara, tells him Indra feeds Sita and that Sita cursed Ravana in a former life, and teaches the nine-night vow of Ashvin, kept before by Vishnu, Shiva, Brahma and Indra. 'Who is that Devi?' Narada describes her. Rama builds an altar on a hill with Narada as priest; on the eighth night the Goddess appears on a lion, names Rama's descent, says Lakshmana will kill Indrajit, promises a long reign and asks for spring worship. Rama does the Vijaya puja on the tenth and builds the bridge.
What is different here:
No hidden lotus and no eye; Narada is the priest; the worship comes before the bridge rather than in the last days of the war.
Sources: Autumn's Awakening: Akal Bodhan of Sri Rama, from the Lanka Kanda of the Krittivasi Ramayana, Sritiochetona (with the Bengali verses); Durga Puja, Wikipedia; Krittivasi Ramayan, Wikipedia; The Srimad Devi Bhagavatam, tr. Swami Vijnanananda (1921-22), book 3, chapter 30: Rama's Navaratri vow