Is it possible for Ichor 30% to mop up some percentage of the...

Is it possible for Ichor 30% to mop up some percentage of the register if the price falls (say 1-10%)?
Also could ichor be permitted to make a deal with Harvest Lane 4% and gain their percentage?
Would they need to advise the market prior or after, if they did the above?
I understand they may need to make an offer to all shareholders if they buy any more shares as they are over 30%, (an offer at the highest price they accumulated 12 months prior)?

If they gain over 50% of the company, can they can take control?
What percentage do they require for a delist, was it 80%?