I've monitored this route over the past 2 yrs. Depends on when seasonal service starts, and what day of the week you want to nonrev. If you're shooting for a cruise, I'd be considering arriving several days prior and having Plan A, B and C. IST might be good choice for backups.
Seriously, check out IST for a few days prior and if you need, Pegasus might have a flight at reasonable cost. It is LCC, so be aware of those pitfalls...Otherwise, TK is prob good option for nonrev.