By now it’s clear that Tesla operates slightly different from most automakers. According to a report from Teslarati owners of the newer (think new grille) Model S P70D sedan actually have a bigger battery in their car than they thought, but the physical 75 kWh pack is limited to 70 kWh via the car’s software. The report alleges that owners of these cars will have the option to call in and ‘unlock’ the extra juice that rests below them, however it comes at a price.

The realization of this battery gimmick is not all that surprising. The new Model X crossover launched with a P75D variant as the base trim level. Given Tesla’s aggressive manufacturing goals, it isn’t a surprise the company is trying to consolidate components and drive additional commonality across their range. Offering both a 70 kWh and 75 kWh pack seems inefficient at best.

According to owners, Tesla has claimed that the option to unlock that extra 5 kWh of battery pack will come at a hefty $3,250 price tag. After the company’s recent earnings report, perhaps the sticker shock associated with this firmware change is not entirely shocking either.

There’s no word yet on what the retail price for the upgrade will be in global markets, however the report alleges that the upgrade will be universal to all Model S sedans that are capable of receiving it. It’s also likely safe to assume the Model S P70D will be discontinued at some point in the near future.