Why the use of the article 'An' instead of 'A' ?
I also pronounce it S P A, so "an" seemed immediately correct to me.
Sounds similar to the battles between es-queue-el and sequel for SQL.
https://abbreviations.yourdictionary.com/reference/abbreviat...
https://www.merriam-webster.com/words-at-play/whats-an-acron...