Ok no finance expert but this is the way I see it.
The club took loans from shareholders to cover debt and stadium finance. These would be repayable at an agreed interest rate.
With the stadium realsied this debt is now being converted.
here is the key. Most of this debt was probably to a small group of shareholders with a large percentage of the shares.
So they have been able to pass probably with some board meeting the conversion of this debt or a portion of it into more shares.
As a club it means the finances of the club dont have to pay off the loans. The loans are now shares that are repayable only on sale of shares. For which the club has no responsibility to buy. Shares can go up or down in value so the shares may make a profit or a loss.
Shares also produce an income from profit. However Saints never turns a profit. But with the new stadium there is every possibility that for a change a profit maybe made and so shareholders get paid a dividend.
With loans being converted to shares this means that current shareholders now have a smaller percentage of the club. Most will not be concerned as they never had a dividend before and just bought shares to help the club.
ie 100 shareholders get more of the profit than 200 share holders. As the profit is split more ways.
So in answer to rouges the only impact will be felt by current shareholders as the profit will be split more ways. But they wont feel that effect with the club having not turned a profit for years.