effect of rating differential in asynchronous games

It seems simple to say the amount by which your rating changes at the end of a game depends on the +/- of your rating vs. your opponent's rating, right? But are we comparing the players' ratings when the game started or when the game ended? Hypothetical situation: 1. You are matched up with Bob who is rated +50 higher than you. 2. The game looks like a draw, so you offer Bob a draw. 3. You expect your rating to increase for a draw against a higher-rated player. 4. Bob thinks he can win and rejects the draw, as more moves are played. 5, Meanwhile you win several games vs. other people, but Bob loses several games vs. other people. 6. You notice Bob is now rated -50 lower than you. 7. The game between you and Bob becomes a forced draw with only kings remaining. So now your rating decreases and Bob's increases because your draw is now against a lower-rated player? Is that how it works?

no, at the start of the match chess.com will tell you how many pointsyou gain/draw/lose, and even if the ratings change the amounts of points you win/lose will remain the same.