This would be a change in one or both of two places: on the component that shows the current liquidity mining rewards, and/or on the blog post linked where it says “learn more” (currently only the blog post explaining the details for the BNB pool SOV liquidity mining rewards mentions the vesting details).
In the case of adding the info directly to the liquidity mining component in the app, that is a frontend change. Does not technically need a SIP, but if there’s a change you really want to be made and the devs are not prioritizing it you could do a Proclamations track SIP to try and get the developers’ attention with a strong signal from the community that this should get done. As a first step I suggest creating an issue in the frontend repo describing the problem and your proposed solution (if you have one). Worse comes to worse, if the devs do not prioritize fixing the problem, and you know how to fix it, you can submit a pull request on GitHub making the change yourself and see if the devs will merge it.
In the case of adding the info to the blog post that is behind the “Learn more” link, that is a change that someone who has access to editing the blog posts needs to make. @TheGimp might know who the right people to ask about this are. Again, does not technically need a SIP, but you could do a Proclamations track SIP to get the blog editors’ attention if they aren’t making a change that you’d like to see.
In terms of what does technically need a SIP, these are proposals that fall into one of three categories: contract source code updates, contract parameter updates, and treasury withdrawals. Edit: One more category to add here, new Origins listings need a SIP too.