It is believed the update centres on the camshaft, though initial speculation suggested the update was related to the MGU-K.
To further confuse the issue, the FIA revealed today that Sebastian Vettel and Kimi Raikkonen will both have new engines (ICE) this weekend as well as new MGU-Ks, though it is claimed the MGU-Ks are merely replacements and not updates.
With the Maranello team unwilling to give much information away regarding the update, it is believed the camshaft change could be linked to a new oil Shell is providing.
The update leaves Ferrari with just 3 tokens for the remainder of the season.
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