Hi Johan,
Bad weather has killed more than one of my trips. I've fished Northern Oman twice and just south of Salalah once. This time of year the weather can be unpredictable. I'll be heading to Southern Oman for a GT charter 22-28 April, hotter temp's but calmer weather. Chatted with the charter captain last week, there is one seat available. Cost is 3100 euro for 7 days of fishing. I'll be heading down a couple of days before the charter to do some shore casting. Decent snapper, queenies, and bluefish also with a chance to bag GT's from shore. Good luck on your next trip.
Cheers
PS If you decide to head back to Oman, sometimes all black poppers or stickbaits have worked wonders in the past.