That's really worth nothing in my opinion, I don't expect RB engines to explode in the next races. We need aero advantage, and RB are masters on that and they are way ahead, plus their usual tricks.
Having a an engine one race newer is worth approx tenth a lap on average, iirc (against your own engine a race older, of course. It doesn't slow anyone else down). Which is not to be sniffed at.
There is another thing now to be optimistic, 2nd position on the WCC, that's a more realistic target than the WDC, but I will never cease to support the team, hope is the last thing to die.
There are far more variable, and more competitors for the WCC. two other teams, two cars in each, 4 races, 24 direct variables, each multiplied by pit stop, start risk, overtaking risk, reliability, and all the rest. Versus two cars facing all that for the WDC. SO, actually, the WDC may be an easier goal to aim for from here. Less to control, less can go wrong, and a clear target on who to beat. Not saying it will be easy, but it is possible, and can be planned for more easily than the WCC.