On to Lošinj, past the bridge at Osor
Between Merag and Mali Lošinj sits a swing bridge that closes the road twice a day. It is the second place on this journey where you wait, and no ferry timetable mentions it.
Updated
Cres and Lošinj are two islands only in name. A channel barely wider than a canal separates them at Osor, and a small swing bridge carries the road across it. That bridge is the reason a crossing of 25 min can turn into an afternoon.
The openings
The Županijska lučka uprava Mali Lošinj, the port authority responsible for it, states the schedule plainly: the swing bridge opens every day at 09:00 and 17:00.
While it stands open, boats pass through the channel one at a time and the road is closed. Regional reporting puts the interruption at 20 to 30 min, stretching further in summer when several vessels are queued. The authority publishes the times but not a duration, so treat the length as an estimate.
Why it collides with the ferry
Merag to Osor is 47 km, about 54 min on the island road. Put that next to the sailing times and a pattern appears: a ferry leaving Valbiska at 15:15 arrives at Merag at 15:40, which puts you at Osor close to 16:34, before the opening. The 16:45 sailing puts you there at about 18:04, after it.
The one in between is the problem. The planner on the home page works this out for whichever sailing you are aiming at, and colours the result.
The weight limit
The bridge carries a limit of 20 t. Anything heavier cannot reach Lošinj by road at all, no matter which ferry it came in on, because there is no second crossing.
For a motorhome or a car with a caravan this is not a practical concern. For freight it decides the route entirely.
Distances beyond Osor
Osor sits at the southern end of Cres. From there the road continues through Nerezine and Veli Lošinj to Mali Lošinj at the far end. The whole run from Merag is a single-carriageway island road with a good deal of climbing, so plan on it taking longer than the map suggests.
If you are coming from the other ferry, at Porozina, the drive to Mali Lošinj is 87 km and about 2 hrs, against 70 km and roughly 1 hr 25 min from Merag. The comparison of the two routes sets that out.
A note on the second bridge
There is a further movable bridge at Privlaka, at the entrance to Mali Lošinj. Sources disagree about whether it still opens: the port authority lists times of 09:00 and 18:00, while regional reporting says it no longer does. Until that is settled this site makes no claim about it.