Apologies if I missed an earlier mention of what seem to be decent TP prices for Catania flights compared to Malta pricing over summer. Google flights showing (and BA site offering):
160TP Gatwick-Catania return as low as £271 (£1.69 / TP) from May to October.
240TP Jersey-Gatwick-Catania return as low as £349 (£1.45/TP) in May / June /October or £373 (£1.55/TP) from May - October.
Or £1.35/TP if you can travel 3-5 May, 9-11 May or 17-19 May when the JER-CTA return is £323.
3 May 13:55 JER > 14:55 LGW / 16:55 LGW > 21:00 CTA
5 May 12:25 CTA > 14:45 LGW / 17:40 LGW > 18:45 JER
All flights above in I bucket, BA site pricing at £322.58