Kalsi wrote:Can someone explain me why not all the engines should get the upgrades from the tokens or link me some regulations about that?
If we were to point you to the official technical regulations, we'd actually be showing that all tokens needs to be applied across every car at the same time.
However, this is not applied in practice, not since the loophole of in-season development was discovered. The loophole on its own brought issues with PU allocations. As you know, each car has 4 allocations of each PU component, across the season. You cannot apply updates on a used/current allocation, as such is considered to be repairs, which are by regulation forbidden (and that is applied in practice). Now, if for some reason a car needs a new PU allocation, ahead of a normal 5 race lifespan, this will bring said car out of sync with the other cars having the same PU supplier.
Example:
-Mercedes the manufacturer plans to bring updates to the MGU-K at the Belgian Grand Prix, the 11th race. If all goes perfect, not a single Mercedes-powered car is faced with a MGU-K failure, the 3th allocation (of 4) of the %GU-K will be injected at the Belgian Grand Prix, so the right time to introduce the update.
Assume however now that for instance Force India faced a broken MGU-K in Bahrain, having to switch to the 2d allocation after 3 full race weekends, instead of 5, meaning the 3th allocation will be introduced at the 7th race. But obviously the update is not ready at that point. Being forced to switch to the 4th and allocation, without the option to keep using the older 2d and 3th allocation, right at the middle of season will be disaster.
So there you have it: Not all the PUs are getting the updates at the same time due to malfunctioning, or even simply strategically injecting a new PU component allocation earlier on, putting them off the planned introduction date. Updates can't be applied on PU component that were used or are current in use, so to make things atleast a bit more managable for the teams they can choose to keep using an old spec of the PU component until they feel the time is ripe. They are even allowed to inject a PU allocation with the token updates, and later on reusing the older allocation with the older specification.
A real life example is the situation Renault customers are in.