To give you an idea, take a look at a mock-up of the new interface:
As you can see, you’ll be able to enable and disable the tool with just one click, set your Maximum Expenditure (the percentage of your budget to spend on Related keywords), and aim the tool to find related keywords likely to bring more conversions.
The percentage you set will determine how actively new related keywords are added to your campaigns, so the “Keyword selection modes” option will no longer be available. The more you are willing to spend, the more relevant keywords Yandex.Direct will find. Limiting your spend on related keywords will likewise provide you with a minimal selection mode.
Where does the “Maximum expenditure” come from if I only enabled “Related keywords” in my campaigns? Before the launch, your current spending on relevant keywords (as a percentage) will become your limit in the new interface. Let’s say, for example, that 300 ₽ of your 3000 ₽ budget currently goes to Related keywords. In the new interface, your limit will be 10%. If you prefer, you can switch in advance from “Relevant keywords” to “Impressions for additional relevant phrases” in the current interface and manually set a percentage of your expenditures. In this case, your settings will be applied in the new interface.