Brit working in Saudi

Hello,

I have a slight problem when it comes to my Vuag and Vwrp buys being rejected.

Looking at the timezones, when its 8am in the usa, its 6pm in saudi and 4pm in the uk. I feel sandwiched and pressured to make a buy before the 4:30 close in the uk and open in usa.
Ive tried making trades at 3.55pm uk and usa its 7.55am and it works. I thought uk markets or offices close at 4:30… even then the timeframe is so short and not the best buy opportunities.
Do i have this wrong, any ideas?..