Nearly all researchers across the company were laid off in 2015. This is the second time the company has taken such a U-turn on R&D. After a decade of frivolous spending on renewable energy, the company abandoned the effort completely. There is a top-down change in strategy every few years which leads to a lot of wasted effort. The company has a serious identity crisis. In the past the company could tolerate this waste and a huge overhead because of low oil prices and few competitors. Today the national oil companies (e.g. Aramco, Petrobras) and smaller leaner companies are pretty much up to speed on oil exploration and refining. Without research and development, BP has very little to bring to the table going forward.
The layoffs have also created an hourglass demography with a lot of well-connected old men and some new graduates, but very few experienced young people. With such a demographic there is very little organic change and continuous improvement - which may explain why there is a top-down reorg every few years. These reorgs always push out the middle demographic which perpetuates the problem.