In sura Ahqaaf Ayat 4 why is the word 'utooni' after samaawaat (there is waqf) pronounced as ietooni?

Question
In sura Ahqaaf Ayat 4 why is the word 'utooni' after samaawaat (there is waqf) pronounced as ietooni?
Answer
In surah Al-Ahqaaf, aayah four: ,  we have the word .  This word starts with a hamzah al-wasl in a verb and third letter has a dhammah, but this dhammah is not an original dhammah in the make up of the word, but instead a product of some letter combinations  and a plural wow.  This caused the ta' to take on a dhammah, even though that is not the original vowel.  We then start this word with a kasrah, as that is the proper vowel for the hamzah al-wasl which has a presented dhammah instead of an original one as the vowel on the third letter, and the second hamzah becomes a ya'. 
The original word is
For more information please see:
http://www.abouttajweed.com/index.php/tajweed-rules/56-hamzah-al-wasl/71-hamzah-al-wasl-lesson-3