The 5/4 roster isn't universal and some bases are 5/3. The 5/3 pattern seems to apply to seasonal bases, reverting to 5/4 come winter. The likes of Malaga, Faro, Trapani, Alghero etc operate this way.
As for a typical roster pattern - there isn't one. You can expect to be busy come the summer schedule and less so come the winter schedule. There are all sorts of variables beyond this. Too many to go in to!!
Summer, so far, has been 4 days of flying and one standby. Occasionally 5 full days have appeared. Other bases can and do offer less, depending on their size. Come winter, 2 to 3 days a week. Again, it can be less. Capacity appears to be further reduced this winter as the airline becomes more seasonal.
Sorry I can't be more definitive, however with no particular system in place, you unfortunately can't be. I can't tell you what bases are busiest, what are quietest, who works most, who works least. You take your chances.
The hard facts are these.
As a FO, you won't fly 900 hrs per year - it's difficult to exceed 750 in my opinion. The regularly quoted figures vary from 600 to 700 per annum.
The company holds more FOs than necessary; this becomes very apparent come winter. Above all, you are a source of revenue via the SSTR.
Best of luck and above all enjoy (there are plenty of positives by the way - I'll let you discover these for yourself should you join
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