Ann: Resignation of Dr Alastair Hodges, page-4

There's a pattern...new Chair Aug17 (Viburnum), new Directors, new CEO Oct17 (ex Siemens), two key scientific staff leave mar/April18. So you could deduce (rightly or wrongly) a determined change of direction from the top or determined change from established old guard. Sometimes the latter can be a handbrake on improvement, and sometimes a handbrake on stupidity.
However, the Annual Report lists a key risk as retention of key scientific staff and that it is extremely hard to attract new relevantly skilled scientific employees. So, all we can say for sure is that there is now a lot more risk about the company's future now.
Interestingly, the recently retired Chair and Directors, and two science staff who have left, combined have >10% of shareholding, so if there is a move to combine with Siemens, a blocking stake of pissed-off ex "insider"shareholders could exist.