I'm just saying there are four bus companies. Three are private and only function during the tourist season, and that includes Turmo. Reliability tips are not going to be useful because it's a day by day thing, but reliability is the norm.

We mentioned interruptions. Having worked in Long Island, New York during May and June, I used that as an example that interruptions were constant, almost daily, due to frequently broken down trains related to outdated infrastructure. If there is a break down at Penn Station dozens of train stations get delayed across the system.

In Sardegna, buses and trains are reliable, but things can happen and no one can assure you otherwise. If they call a transportation strike in Rome it's not predictable which company will decide to go along in solidarity in Sardinia.

Any one person's experience is a one-off.

All you can do is trust the system, and realize that public transportation in Italy is generally very reliable. There are no guarantees beyond that. Go with it, but know the back up options. If someone went 5 times on that trip their report is statistically meaningless if interruptions occur oncer every 20 times.

If you go to Olbia's website, they list the strikes that are upcoming.
There was a strike June 16th.
http://www.geasar.com/deu/flughafen/...ero-16/06/2017

During strikes there is usually a "fascia di garanzia," where things work anyway, so that people can get back and forth to work. Here is an example.
http://www.ilpost.it/2017/06/12/scio...izi-garantiti/

Here is an example of the schedule of upcoming strikes "Sciopero," which are always posted in advance. Make use of them, and have alternative options is all that I am saying.
http://www.cgsse.it/scioperi/Fasce.pdf

In Sardinia there is only going to be a strike in Cagliari. The fascia di garanzia is from 5:30 to 8:30, and from 12:30 to 15:30.

Strikes in Italy are less frequent than breakdowns in NYC, so don't fret. I would tell anybody visiting NYC, San Francisco, or the places in Italy where I frequent to just know their options. I've been at JFK where I couldn't get a taxi into NYC: there were just none available. But I knew my options. That has happened to me in Rome, Venice, and everywhere else.

One-offs of someone saying that they used Turmo and it great are nice, but I don't think it provides much helpful info. I took it that the question was not about the 95% of the time when everything is nice, but what do you do the other 5% of the time? You have options.