Doo wrote:Hi Noajthan and thank you for the reply,
So even the reason of leaving is work related and it is frequent from UK to KSA on regular basis ?
The regulation says:
Continuity of residence is not affected by —
(a)periods of absence from the United Kingdom which do not exceed six months in total in any year
It doesn't mention any reason (work or otherwise), so there's no allowance for going for work.

You would have to keep careful track to make sure you don't go over the limit.

And be aware, if you ever have plans to apply for the privilege of citizenship, the rules & limits are different for naturalisation.
You would not qualify to naturalise if absent for half of every year;
for example, the permitted limit in final year before applying to naturalise is only 90 days.