TL;DR: On December 15, all remaining offsite investments will be removed and the commission rate will become dynamic based on the bankroll's size. This is currently beneficial for investors as it will lower the commission rate, but will disincentivize the bankroll becoming larger in the future. Players are not affected.
When I increased the bankroll commission to 50% of the expected profits in September 2019 I had hoped to reduce the size of the bankroll and therefore the total amount of investors' money bustabit and bustadice are responsible for. However, one year later the combined bankrolls still total more than 11,000 BTC. To more actively manage the size of the bankrolls I will be making two changes effective December 15:
First, offsite investing will be retired completely. This will immediately reduce the size of the bankrolls by more than 4,000 BTC and is also in the interest of fairness towards the majority of investors who did not have the opportunity to invest offsite. All remaining offsite investments will be eliminated and affected investors will receive an equivalent amount of dilution fee credits.
Second, bustabit and bustadice will both move to a dynamic commission model where the commission changes in real-time based on the size of the bankroll:
commission rate = bankroll / 10,000 BTC
On bustabit this means that the commission rate will be roughly the same as now or slightly lower. On bustadice these changes slash the commission by more than half, down to ~20%.
This is very disappointing. Retiring the offsite part is very bad, it reduces drastically the expected returns for those investors that have trusted in your project for a long time, before Bustabit had the impressive track record that it currently has. By simply not allowing people to add anything to the offsite portion, over time, the offsite/onsite ratio would decrease, without having to penalize those investors that helped you make this such a successful project. Increasing the fee last year was annoying enough, but this is effectively reducing expected returns by up to 2/3.
Other than not letting people increase their offsite portion, the fair way to approach this situation would have been to gradually increase the dilution fee. This should limit the bankroll's growth without harming early investors. Another more extreme approach, but that you could consider, is simply not allowing new investments at all, but I think increasing the dilution fee is the fairest method by far. I'd also expect some of that dilution fee being cashed out by investors receiving it, so that you'll also achieve your goal of limiting the bankroll's size.
About making the comission variable, I think that's a mistake too, as it makes it harder to estimate which are the expected returns. And obviously, if we get over 5,000 BTC bankroll, fees would be even higher than now, on top of not even being able to keep our offsite portion.
Please reconsider this point, you can achieve the same goal without damaging previous investors. I'd suggest you to try increasing the dilution fee, so that new investments are still allowed but new investors at least pay a premium for the privilege of joining this project when it's already mature. What you are proposing here is the opposite, penalizing previous investors.