Indeed, Dudley has contributed a lot to the company and was...

Indeed, Dudley has contributed a lot to the company and was instrumental in bringing San Anton to where it is today. It is sad to see him go. But I understand he has not been very well physically for some time.
The recent share price drop, I believe, was triggered by a new that a few people may have heard about---the abbatoir owned by Dudley had gone into voluntary receivership.
It was reported in the local newspaper of the town on Mon.
Fearing a major dump of share by Dudley, some shareholders must have pre-empted by selling down their portfolio.
If he needs to sell, I don't think the quantity of shares he owned can be dumped into the open market.
If he needs to off load, someone else will probably buy it off him in an off-market transaction.