As a previously orange, now BA short haul pilot I feel duty-bound to chime in and concur with the above warnings. easyJet may have its gripes but do not fall into the greener grass trap as I did, nor for that matter any of the absolute garbage you may read in the job adverts about them "listening and caring", or switching fleet "when it suits your career" (read: when and IF it suits BA).
The harsh reality is that JSS will decimate your lifestyle, you'll have a perpetual basic pay cut of anywhere between 4 and 10% per month (but they won't tell you until the day before payday), and you'll likely find yourself participating in industrial action in the not-too-distant future. All with now markedly less job security.
I wholeheartedly agree with the above - if you need to return to the UK, go for it. If you're in a half decent outfit already, then you'll be in for a shock.