Proposals are renumbered throughout the Proposal, Counterproposal, and Sponsorship Phases, as well as immediately prior to the Voting Phase. This is because proposers often get the numbering wrong and skip numbers (or create multiple proposals with the same numbers), and because proposals get vetoed, withdrawn, or fail to get a sponsor.
If you reference a proposal without linking to it, e.g., "Proposal 30a", you have no guarantee that the number won't change, and anyone reading the conversation later will potentially be confused.
If you make reference sheets which just use the numbers and don't include links to the proposal threads, you might confuse yourself.
Instead, if you want to talk about a given proposal, link to it in your post.
If you reference a proposal without linking to it, e.g., "Proposal 30a", you have no guarantee that the number won't change, and anyone reading the conversation later will potentially be confused.
If you make reference sheets which just use the numbers and don't include links to the proposal threads, you might confuse yourself.
Instead, if you want to talk about a given proposal, link to it in your post.