As Ven. Nyanatiloka writes:
For example, in Anguttara Nikaya 9.47-49 we find identical definitions of 'Sandiṭṭhikanibbāna', 'Nibbāna' and 'Parinibbāna':parinibbāna - 'full Nibbāna', is a synonym for Nibbāna;
this term, therefore, does not refer exclusively to the extinction of the 5 groups of existence (khandha) at the death of the Holy One, though often applied to it.
http://www.palikanon.com/english/wtb/n_ ... bbaana.htm
(English translation by Sister Upalavanna is available at http://awake.kiev.ua/dhamma/tipitaka/2S ... ggo-e.html )6. Sandiṭṭhikanibbānasuttaṃ
47. “‘sandiṭṭhikaṃ nibbānaṃ sandiṭṭhikaṃ nibbānan’ti, āvuso, vuccati. kittāvatā nu kho, āvuso, sandiṭṭhikaṃ nibbānaṃ vuttaṃ bhagavatā”ti?
“idhāvuso, bhikkhu vivicceva kāmehi ... pe ... paṭhamaṃ jhānaṃ upasampajja viharati. ettāvatāpi kho, āvuso, sandiṭṭhikaṃ nibbānaṃ vuttaṃ bhagavatā pariyāyena ... pe ....
“puna caparaṃ, āvuso, bhikkhu sabbaso nevasaññānāsaññāyatanaṃ samatikkamma saññāvedayitanirodhaṃ upasampajja viharati, paññāya cassa disvā āsavā parikkhīṇā honti. ettāvatāpi kho, āvuso, sandiṭṭhikaṃ nibbānaṃ vuttaṃ bhagavatā nippariyāyenā”ti. chaṭṭhaṃ.
48. "'Nibbānaṃ nibbāna'nti, āvuso, vuccati…pe…. Sattamaṃ.
49. "'Parinibbānaṃ parinibbāna'nti…pe…. Aṭṭhamaṃ.
In AN 4.169 we find a mention of someone (ekacco puggalo) attaining Parinibbana in this very life (diṭṭheva dhamme):
(for English translation see http://awake.kiev.ua/dhamma/tipitaka/2S ... ggo-e.html )ekacco puggalo diṭṭheva dhamme (s)asaṅkhāraparinibbāyī hoti
Steven Collins writes in his book "Nirvana and Other Buddhist Felicities":
Metta, Dmytro(3) The words parinirvāṇa and parinibbuta. It has been claimed that there is a specific grammatical distinction between these terms and nibbāna/nibbuta. Thomas (1933: 121-2 n. 4), attributing the idea to E. Kuhn, stated that: "Pari compounded with a verb converts the verb from the expression of a state to the expression of the achievement of an action: nirvāṇa is the state of release; parinirvāṇa is the attaining of that state." In a later work (1947: 294-5) he also claimed that a person parinibbāyati, attains the state, and then nibbāyati, is in the state expressed by nibbāna." The way the terms are used, however, does not support his view: the two are interchangeable, in both literal and metaphorical-religious senses. Commentaries give the terms as explanations of each other.