As Clive has said your choices are clear you just need to get on with it.either invest in a opico type dryer and simple store - circa £150k should do it to a practical level for 900ac
or sell for harvest movement as is and take the moisture claims
or find a local commercial store to send it to and accept charges
use whatever income the existing sheds are bringing in to offset cost of the above ?
don’t buy CS - it makes no sense vs using commercial stores with no buy in
If cashflow wont allow a new building then selling at harvest will be on par with what you are currently doing.