For the most part, the adventures aren't substantially changed from the scenarios in terms of structure, so I assume they'd run about the same time.
I ran the first adventure ("The Commencement") for my home group this past weekend, and it ran pretty much about the same length as the original scenario. Perhaps shorter than usual for this one, as the notoriously time-consuming junkcycle race was replaced with a starship combat.
I plan to post about the AP in my blog as we go through it. The first installment is here. These posts won't be as in-depth about the events of each session as some of my past campaign journals have been, since this is an AP based on popular SFS scenarios, rather than a homebrew game. But I will definitely comment on how things went where the AP and/or I deviate from the original scenario. For example, this first installment talks about my decision to use the narrative starship combat rules, because the standard rules are my least favorite thing to GM in Starfinder, and my players' least favorite part to play. (Short answer: resounding success, both IC and OOC!)
I've now run Parts 2 and 3, and the run time continues to be right about the 4-5 duration of the original adventures. My home group is more comfortable with 4 hours at a time, so I still have some work to do to get better at pacing to finish in that time. The final fight for Part 3 was long and nasty, so pushed us to around the 5-hour mark (and everyone was exhausted IC and OOC by then).
On the other hand, this an AP for a home game, so we can break an adventure into two sessions if we ever need to. I expect I'll need to with a few of them, especially at the higher levels.
Parts 6 and 12 are conversions of multi-table specials, and allow (and expect) the PCs to play through ALL the available content, which you can't always do during a strictly-timed special. The authors suggest these will each take two 4-5 hour sessions to play out. I'm expecting to need a minimum of three for each with my group's schedule.
Well, as of last night I can officially say that running this adventure path took my group exactly five years and nine months to complete. But we included a few bells and whistles.