Discussion on answer by Sabrina: Nós estamos - how to pronounce the "s"

@Lambie aren't you just referring to BP/Pt-Br? I'm referring to European Portuguese (as befits the question), which has very different phonotactics from BP. If you watch this Portuguese ad (youtu.be/EQDtlGzsTsA), which isn't spoken slowly or formally, you can hear that the first 'e' in 'estiver', 'estares' and 'estávamos' aren't pronounced. For more formal proof, you may refer to the Blackwell Handbook of Portuguese Linguistics, chapter 6 Syllable Structure ("The prosthetic vowel that is obligatory in word‐initial ##sC clusters in BP is dispensed with in EP")

No. Word-initial 'e' can be elided. For example, the transcription given in Leo Wetzels's book for espaço, esfinge, esbirro and esmagar is [ʃpásu], [ʃfĩʒ], [ʒbiru] and [ʒmɐgáɾ]. These "consonant clusters [...] are derived by rules of unstressed vowel deletion which create surface exceptions to the constraints of core syllabification." Wetzels et al are professors of linguistics in Brazil, Portugal and beyond so I believe they are credible. Plainly speaking, you have not given any formal proof or argument about syllable structure, nor even used IPA.

Once again, from one of the leading books on Portuguese linguistics: "The prosthetic vowel that is obligatory in word‐initial ##sC clusters in BP is dispensed with in EP" = the 'e' can be deleted. The dictionary Schilive mentions (which is Portugal-based) gives /(i)ʃˈpasu/. The brackets mean that pronouncing /i/ is optional. Which means that it is possible to not pronounce the 'e'.

Sabrina, yeah, you're right. I'll delete my comment. By the way, I am not Lambie, I'e never touched that question. My full name is "Herr Gabriel Schilive von Neumann Schmidt Schöneste Mann der Welt und des Universums homo bellisimus mundique universi Cândida do Amor Divino".